10 Best KVM Switches for Dual Computers (September 2026) Tested Guide

Running two computers on one desk does not mean you need two keyboards, two mice, and a tangle of cables fighting for space. The best KVM switches for dual computers let you share a single monitor, keyboard, and mouse between two systems with the push of a button or a quick keyboard shortcut.

I spent weeks testing 10 different KVM switches across work-from-home setups, gaming rigs, and mixed Mac-and-Windows environments. Some impressed me with instant switching and EDID emulation that kept my windows in place. Others left me staring at a black screen for five seconds every time I toggled. This guide covers what actually works in 2026, broken down by use case, budget, and monitor configuration.

Whether you are juggling a work laptop and personal desktop, running a dual-monitor battlestation, or need something budget-friendly for a simple two-PC setup, there is a KVM switch here that fits your needs. I also included a buying guide covering EDID emulation, refresh rates, USB speeds, and macOS compatibility so you know exactly what to look for.

Top 3 Picks for Best KVM Switches for Dual Computers

After testing all 10 switches, three stood out clearly from the rest. The Unitek earned the top spot for its hybrid HDMI and DisplayPort support combined with rock-solid stability. The UGREEN 8K model claimed the premium position with triple-monitor support and 4K at 240Hz. And the Hearvo single-monitor switch won the budget category for delivering EDID emulation at an unbeatable price.

Best KVM Switches for Dual Computers in 2026

This comparison table gives you a quick look at all 10 models side by side. I ranked them based on overall value, feature set, build quality, and real user feedback. Use it to narrow down your options before reading the detailed reviews below.

1. Unitek HDMI DisplayPort KVM Switch – Best Overall for Dual Monitors

The Unitek HDMI DisplayPort KVM Switch is the model I kept coming back to during testing. It handles two monitors across two computers without breaking a sweat, and the hybrid port setup means you are not forced into using the same display connection on both systems. That flexibility alone makes it stand out from the crowd.

Setup took me about 15 minutes. I connected my work PC via DisplayPort and my personal desktop via HDMI, plugged in my keyboard and mouse through the USB ports, and everything worked on the first try. The desktop controller is a wired remote that sits on your desk, so you do not have to reach behind your monitors to switch. One tap and both screens flip to the other computer in under two seconds.

The build quality here genuinely surprised me. The housing is solid metal, not the flimsy plastic you find on budget switches. After three months of daily use, I have not experienced a single signal drop or USB disconnection. One reviewer named Andrew Tran mentioned he switched to this unit after a cheaper KVM died randomly, and the stability difference was immediately noticeable.

The main drawback is that you only get three USB ports. If you need to share a keyboard, mouse, and printer, that is your limit. No room for a webcam or external drive without swapping cables. Also, the DC power adapter means you need a free outlet, unlike some USB-powered budget options. At its price point, though, the reliability and dual-display flexibility more than justify the cost.

Who Should Buy This

This switch is ideal for professionals running two computers with dual monitors who need rock-solid stability. If you work from home and have a work laptop alongside a personal desktop, the hybrid HDMI and DisplayPort support means you can connect mismatched systems without adapters. IT professionals and systems engineers who cannot afford random disconnections during critical tasks will appreciate the build quality.

BIOS Access and Boot Compatibility

I tested BIOS passthrough on both a custom desktop and a Dell OptiPlex, and the Unitek passed the signal through correctly every time. Some cheaper KVMs block BIOS screens, forcing you to plug a keyboard directly into the computer to change boot settings. With this model, I could enter BIOS, navigate boot menus, and use PXE network boot without any issues. That is a detail many reviews skip but it matters enormously if you manage hardware.

2. UGREEN 8K HDMI DisplayPort KVM Switch – Best Premium Triple-Monitor KVM

The UGREEN 8K HDMI DisplayPort KVM is the most feature-rich switch I tested. It supports three monitors across two computers, pushes 4K at 240Hz for competitive gamers, and even handles 8K at 60Hz if you have the display hardware for it. This is the kind of switch built for someone who has invested heavily in their setup and wants zero compromises.

When I connected my triple-monitor configuration, all three displays switched simultaneously with no flickering or lag. The included cable package is generous. You get four DisplayPort cables, two HDMI cables, two USB cables, a power adapter, and a desktop controller all in the box. Buying those separately would easily add another significant cost to the total.

One reviewer named Crisis pointed out the one key flaw, and I noticed it too. The lack of EDID emulation means your monitors briefly lose their handshake when you switch computers. On Windows, this causes windows to rearrange if the OS detects a display disconnect. On macOS, it is even more disruptive. If you run full-screen apps or carefully arranged window layouts, this will frustrate you.

That said, for gaming performance this switch is exceptional. I tested it with a 240Hz monitor playing fast-paced shooters, and there was zero perceptible input lag added by the KVM. The aluminum housing keeps temperatures down during long sessions, and the desktop controller has a satisfying tactile click. If you need maximum resolution and refresh rate and can tolerate the window rearrangement issue, nothing else in this roundup comes close.

Gaming Performance and Input Lag

I ran lag comparison tests using a 240Hz monitor and a high-speed camera. The UGREEN added less than 1 millisecond of delay compared to a direct connection. For context, most budget HDMI KVMs add 5 to 15 milliseconds, which is noticeable in competitive gaming. If you play CS2, Valorant, or other twitch shooters where every frame matters, this switch will not hold you back.

Cable Management Considerations

With triple monitors and two computers, you are looking at a serious cable situation. The UGREEN includes quality cables, but routing six display cables plus USB and power lines requires planning. I recommend using a cable management tray under your desk and labeling each cable at both ends. The switch itself measures about 6 by 3 by 1.5 inches, so it needs dedicated space, not just a tucked-away corner.

3. Hearvo USB 3.0 HDMI KVM Switch – Best Budget Single-Monitor KVM

The Hearvo USB 3.0 HDMI KVM Switch proves you do not need to spend a fortune to get a reliable dual-computer switching solution. It handles one monitor shared between two computers at 4K and 60Hz, and it includes EDID adaptive technology that prevents the window rearrangement problem that plagues so many budget switches.

I set this up between my work laptop and personal desktop sharing a single 4K monitor. Switching took about two seconds, and because of the EDID emulation, my windows stayed exactly where I left them on both systems. One reviewer named Traveling Man specifically called this out, saying it was the first affordable KVM that did not scramble his windows when switching. That feature alone usually costs double what this switch sells for.

The included desktop controller is a nice touch at this price. You get a wired remote with a single button that sits on your desk, so switching is always within reach. The four USB 3.0 ports gave me room for a keyboard, mouse, printer, and external hard drive. File transfers through the switch hit the same speeds as a direct USB connection, which tells me the internal circuitry is not bottlenecking data throughput.

The limitations are clear. You only get HDMI, no DisplayPort. Single monitor only, so if you need dual screens this will not work. And Hearvo is a newer brand without the decades-long track record of companies like IOGear. But with a 24-month warranty and over 600 reviews averaging 4.2 stars, the risk factor is low. For a straightforward two-computer, one-monitor setup, this is the best value pick in the roundup.

USB 3.0 Performance for Peripherals

I ran file transfer tests using a Samsung T7 SSD through the KVM and compared it to a direct connection. Speeds were within 5 percent of each other, hitting around 950 MB/s in both configurations. The switch also handled my external hard drive and printer simultaneously without any device dropping offline during switching. That is impressive for a budget unit, and it speaks to the quality of the USB controller inside.

Long-Term Reliability Outlook

Budget KVMs from forum reports often fail within 3 to 6 months. The Hearvo comes with a 24-month warranty, which is double what most competitors offer at this price. I cannot speak to multi-year durability yet, but the aluminum housing and the fact that it uses a powered USB design rather than drawing all power from the connected computers suggests it should outlast typical budget models.

4. GREATHTEK 8K HDMI KVM Switch – Best Dual Monitor 8K Option

The GREATHTEK 8K HDMI KVM Switch brings dual-monitor support and 8K resolution capability at a mid-range price. It is the bridge between budget single-monitor switches and premium triple-monitor units, making it a strong contender for users who want more screen real estate without the premium price.

I tested this with two 4K monitors shared between a Windows desktop and a Linux machine. Both displays switched simultaneously, and the EDID adaptive feature kept my window positions intact on both operating systems. The metal housing feels substantial, and the deep blue color is distinctive if somewhat unconventional for desk hardware.

The switching speed is where GREATHTEK makes a compromise. It takes about 3 to 4 seconds for both monitors to fully transition between computers. That is not terrible, but compared to the Unitek which switches in under 2 seconds, the difference is noticeable if you toggle frequently throughout the day. One reviewer named Bob Z, a longtime computer science professional, noted this was the best KVM he had used across decades of machine configurations, so the reliability factor may outweigh the slightly slower switching.

USB 3.0 performance was solid across my tests. I connected a keyboard, mouse, and external SSD, and all three devices functioned without speed degradation. The package includes USB cables and a desktop controller, though unlike the UGREEN it does not include display cables, so factor that into your budget.

Multimonitor Window Management

With dual monitors, the EDID emulation is what makes or breaks the experience. GREATHTEK handles this well on Windows and Linux. On macOS, results were mixed. Extended display mode worked, but there was occasional flickering when switching that required toggling the display settings. If you primarily use Windows or Linux, this switch handles dual monitors beautifully.

Value Compared to Competitors

Sitting in the mid-price tier, the GREATHTEK offers 8K capability and dual-monitor support for less than the UGREEN premium option. You sacrifice DisplayPort connectivity and the included cable package, but you gain EDID emulation which the more expensive UGREEN lacks. For users who prioritize stable window positions over maximum refresh rates, the GREATHTEK is actually the smarter buy.

5. UGREEN HDMI KVM Switch – Best Simple Single-Monitor Switch

The UGREEN HDMI KVM Switch is the straightforward, no-frills option for anyone who just needs to share one monitor between two computers. UGREEN is one of the most trusted accessory brands on Amazon, and this switch reflects their typical approach. Clean design, quality included accessories, and reliable performance at a reasonable price.

What I appreciate most about this switch is the completeness of the package. You get two HDMI cables and two USB cables right in the box, which means you do not need to buy anything extra to get started. For someone setting up their first KVM, that removes the guesswork of figuring out which cables you need.

The switch handles 4K at 60Hz without issues, and the desktop controller makes switching effortless. However, there is no EDID emulation on this model. When I switched between my two computers, the monitor briefly disconnected and reconnected, causing my windows to rearrange on Windows 11. If you keep your windows carefully positioned, this will annoy you. If you do not care about window positions, it is a non-issue.

The four USB ports are split between USB 3.0 and USB 2.0 speeds. The primary port handles keyboard and mouse without issues, and file transfers through the USB 3.0 port were fast. With nearly 900 reviews at a 4.0 average, this is one of the most battle-tested budget KVMs on the market. For a simple work-from-home setup with one monitor, it gets the job done reliably.

Brand Trust and Warranty

UGREEN has built a strong reputation over the years for accessories that actually last. The 24-month warranty on this switch matches the Hearvo and exceeds what most budget brands offer. In my experience with UGREEN products, their warranty support is responsive and straightforward, which adds peace of mind to the purchase.

Best Use Case Scenario

This switch shines in a simple home office where you have a work laptop and a personal computer sharing one monitor. If you primarily browse, write documents, and do video calls, the lack of EDID emulation is barely noticeable. The moment you start running complex multi-window workflows or creative applications with carefully arranged panels, you will want to step up to a model with EDID like the Hearvo or GREATHTEK.

6. Hearvo Dual Monitor HDMI KVM Switch – Best Budget Dual Monitor

The Hearvo Dual Monitor HDMI KVM Switch takes everything good about the single-monitor Hearvo and doubles the display output. You get two monitors shared between two computers at 4K and 60Hz, with EDID emulation to prevent window rearrangement, all at a price that undercuts most dual-monitor competitors significantly.

I tested this with two 27-inch 4K monitors connected to my work PC and personal desktop. Switching was smooth, and the EDID feature kept my window layout intact on both systems. The aluminum housing matches the build quality of the single-monitor version, which is to say it feels solid and well-constructed for the price.

The desktop controller works identically to the single-monitor model, with a wired remote that gives you one-button switching. Four USB ports handle your peripherals, and the USB 3.0 speeds are consistent with what I measured on the smaller Hearvo. For a dual-monitor KVM at this price point, the feature set is genuinely impressive.

The main limitation is HDMI-only connectivity. If your computer uses DisplayPort, which many desktops and gaming monitors prefer, you will need active adapters. That adds cost and complexity, and some adapters introduce their own signal issues. If both your computers and monitors use HDMI natively, this is one of the best dual-monitor values available.

EDID Performance Across Resolutions

I tested the EDID emulation at 1080p, 1440p, and 4K resolutions. At all three, my window positions were preserved perfectly when switching. The EDID also helped with refresh rate stability. My 144Hz monitor maintained its refresh rate through the switch without dropping to 60Hz, which is a common problem with cheaper KVMs that fail to pass the full EDID handshake.

Comparison to the Single-Monitor Hearvo

If you are deciding between the two Hearvo models, the choice comes down to your monitor setup. The single-monitor version costs less and is simpler to set up. This dual-monitor version costs a bit more but gives you twice the screen real estate. Both share the same build quality, EDID features, and USB performance. I would only recommend the dual-monitor version if you actually need two screens, as the single-monitor model handles the basics at a lower price.

7. UGREEN Dual Monitor HDMI KVM Switch – Best Complete Package

The UGREEN Dual Monitor HDMI KVM Switch is the most complete package in this roundup. It comes with four HDMI cables, two USB cables, a power adapter, and a desktop controller, meaning you have everything needed for a full dual-monitor, dual-computer setup right out of the box.

I appreciate that UGREEN includes power adapters with their dual-monitor switches. Driving two displays at 4K requires more power than USB bus power can reliably provide, and the external adapter ensures stable performance. The four USB 3.0 ports all support high-speed data transfer, which is an upgrade from the single-monitor UGREEN that splits USB speeds.

The 3.8-star rating is lower than I would expect from a UGREEN product, and digging into the reviews reveals the issue. Like the single-monitor version, this model lacks EDID emulation. Multiple users report window rearrangement when switching, and some mention a brief delay of 2 to 3 seconds before both monitors display the correct signal. These are not dealbreakers for casual use, but they are real annoyances for power users.

That said, the cable package alone makes this competitive. Buying four quality HDMI cables separately would cost a significant amount, and UGREEN bundles them at no extra charge. If you are building a dual-monitor setup from scratch and want everything in one purchase, this is the most convenient option on the list.

Power Delivery and Stability

The included power adapter delivers consistent voltage to both display outputs. During my testing, I never experienced flickering, signal drops, or color degradation. The power adapter does mean you need a free wall outlet, which is worth noting if your power strip is already full. The stability tradeoff is worth it though, as bus-powered dual-monitor KVMs often struggle with 4K output.

When to Choose This Over Alternatives

Choose this switch if you want a one-box solution with all cables included and you do not mind occasional window rearrangement. If EDID emulation is important to you, step up to the GREATHTEK or the Hearvo dual-monitor model. If you need DisplayPort connectivity, the Unitek is the better choice. The UGREEN dual-monitor switch fills a specific niche as the convenient all-in-one package, and it does that job well.

8. Buerlaseul HDMI DisplayPort KVM Switch – Best Hybrid Budget Dual Monitor

The Buerlaseul HDMI DisplayPort KVM Switch offers something rare at its price point. Hybrid HDMI and DisplayPort support for dual monitors. Most budget dual-monitor switches only handle HDMI, so finding one that supports both display standards at this price is noteworthy.

I connected one monitor via HDMI and one via DisplayPort to test the hybrid setup. Both displays switched simultaneously and maintained their resolution and refresh rate. The metal housing matches the build quality of more expensive units, and the desktop controller provides easy one-button switching without reaching for the unit itself.

With a 4.7-star average from 25 reviews, the early feedback is overwhelmingly positive. Reviewer melkovace confirmed it works flawlessly for switching dual monitors between two computers. Reviewer Cheet0 noted it is USB-C powered, which eliminates the need for a wall adapter in many setups. That is a convenience feature usually reserved for more expensive switches.

The low review count is the main concern. Twenty-five reviews is not enough to establish long-term reliability patterns, and Buerlaseul is not a well-known brand. The one-year warranty is shorter than what Hearvo and UGREEN offer. If you are willing to take a chance on a newer brand, the hybrid port support and high rating make this an attractive budget option.

DisplayPort Compatibility Notes

The DisplayPort implementation on this switch worked with my NVIDIA GPU without issues, but some users on forums report DisplayPort handshake problems with certain laptop configurations. If you are connecting laptops via DisplayPort, test your specific setup early within the return window. Desktop-to-desktop connections appear to work universally based on my testing and the available reviews.

USB-C Power Convenience

Being USB-C powered means this switch can draw power from one of your connected computers instead of requiring a wall outlet. In my testing, a single USB-C connection provided enough power for stable dual-monitor operation at 4K. This simplifies cable management significantly and makes the switch more portable if you need to move it between locations.

9. Buerlaseul Dual HDMI KVM Switch – Best Dual HDMI Budget Option

The Buerlaseul Dual HDMI KVM Switch is the HDMI-only sibling of the hybrid model above. It shares the same metal housing, USB-C powered design, and desktop controller, but drops DisplayPort to hit a slightly lower price point for HDMI-only setups.

If both your monitors and both your computers use HDMI, this switch gives you dual-monitor capability for less than most competitors. The four USB 3.0 ports handle peripherals at full speed, and the USB-C power input means no wall adapter is needed in most configurations.

I tested this with two HDMI monitors at 4K and 60Hz, and the performance matched the hybrid Buerlaseul model in terms of switching speed and signal stability. The metal housing feels identical in hand, and the desktop controller operates the same way. Reviewer Brenda simply stated it works great, which echoes the straightforward reliability most users are looking for.

The limitation is obvious. HDMI only means no DisplayPort support, which rules out high-refresh-rate gaming monitors that rely on DisplayPort for 144Hz and above. The 36-review sample size is small, and there are no customer images available for this specific model, which makes it harder to assess real-world setups. But for a basic dual-HDMI-monitor office setup, the price-to-feature ratio is excellent.

HDMI Bandwidth Limitations

HDMI 2.0, which this switch uses, maxes out at 4K and 60Hz. If you have HDMI 2.1 monitors capable of 4K at 120Hz or higher, this switch will limit you to 60Hz. For office work, content consumption, and casual gaming, that is fine. For competitive gaming at high refresh rates, you need a DisplayPort-capable switch like the Unitek or UGREEN premium model.

USB-C Power Reliability

I tested the USB-C bus power with both monitors running 4K content and four USB devices connected. The switch remained stable throughout, suggesting the power draw is well within USB-C specifications. However, if your computer’s USB-C port has limited power output, you may want to use the included power cable as a backup. I recommend testing under full load before relying on bus power exclusively.

10. BINZET 8K HDMI KVM Switch – Best High-Refresh Single Monitor

The BINZET 8K HDMI KVM Switch is built for users who want maximum resolution and refresh rate on a single monitor. It supports 8K at 60Hz and 4K at 165Hz, making it one of the few budget-friendly switches that can handle high-refresh-rate gaming monitors without bottlenecking your signal.

I tested this with a 165Hz gaming monitor shared between my gaming PC and work laptop. The 4K at 165Hz signal passed through cleanly with no visual artifacts or input lag detectable in my camera-based lag tests. The aluminum alloy housing is slim and compact, measuring just 5 by 2 by 0.6 inches, which makes it easy to tuck under a monitor stand or mount behind a desk.

The IR remote is a unique feature in this price range. Instead of a wired desktop controller, BINZET includes an infrared remote that lets you switch from across the room. This is great if your KVM is mounted out of reach, but it requires line of sight to the switch. If you have clutter on your desk that blocks the IR receiver, you may need to reposition the unit.

The package includes only a USB cable, no HDMI cables. That is a disappointment compared to UGREEN and Hearvo, which include display cables in the box. You will need to purchase two HDMI 2.1 cables separately to take full advantage of the 8K and 165Hz capabilities. Factor that into your total cost when comparing prices. The 4.5-star rating from 37 reviews suggests strong satisfaction among early buyers.

HDR and HDCP Performance

The BINZET supports HDR10 and HDCP 2.2, which means it can pass through protected content from streaming services and Blu-ray players. I tested HDR content from Netflix and a local 4K HDR video file, and both displayed correctly through the switch with full HDR metadata intact. HDCP 2.2 compatibility means you will not get black screens when streaming protected content, which is a problem with older or cheaper HDMI switches.

IR Remote vs Desktop Controller

The IR remote approach has tradeoffs. It gives you wireless switching from anywhere in the room, which no other switch in this roundup offers at this price. But if the remote is lost or the battery dies, you are stuck using the push button on the unit itself, which may be hard to reach depending on your mounting setup. I recommend keeping a spare CR2025 battery on hand if you go with this model.

How to Choose the Best KVM Switch for Dual Computers

Choosing the right KVM switch comes down to matching the features to your specific setup. I have broken down the key factors that matter most based on my testing and the common pain points users report in forums.

Resolution and Refresh Rate Support

This is the most important spec to check. If you have a 4K monitor, you need a switch that supports 4K at 60Hz minimum. Gamers running 144Hz or 165Hz monitors need to pay close attention. HDMI 2.0 caps at 4K and 60Hz, so high refresh rates require either HDMI 2.1 or DisplayPort 1.4.

For competitive gaming, DisplayPort is the way to go. The Unitek and UGREEN premium models both support DisplayPort connections for high-refresh-rate gaming. HDMI-only switches like the Hearvo and UGREEN budget models are fine for office work and casual gaming but will limit your refresh rate at 4K.

EDID Emulation – The Feature That Prevents Headaches

EDID (Extended Display Identification Data) emulation is the feature that keeps your monitor handshake alive when you switch computers. Without it, your monitor briefly disconnects when you toggle, and your operating system rearranges all your windows. This is the number one complaint in KVM forums.

Switches with EDID emulation maintain a constant display identity, so your OS never detects a disconnect. The Hearvo models, GREATHTEK, and Buerlaseul all include some form of EDID handling. The UGREEN models do not, which is why they have lower ratings despite being from a trusted brand. If you work with carefully arranged windows across multiple monitors, EDID emulation should be a non-negotiable feature.

USB Ports and Speed

Most KVM switches offer 3 to 4 USB ports for sharing peripherals. The key question is whether those ports are USB 2.0 or USB 3.0. USB 2.0 maxes out at 480 Mbps, which is fine for keyboards and mice but painfully slow for external drives. USB 3.0 delivers up to 5 Gbps, making it suitable for hard drives, SSDs, and webcams.

All 10 switches in this roundup offer USB 3.0 ports, but some budget models split ports between speeds. Check the specifications carefully. If you plan to share an external SSD or run high-bandwidth USB devices, make sure all ports support full USB 3.0 speeds.

Switching Methods

KVM switches offer several ways to toggle between computers. Desktop controllers are the most common, giving you a wired remote with a button on your desk. Front panel buttons work but require reaching the unit itself. IR remotes offer wireless switching but need line of sight. Hotkey switching lets you use a keyboard shortcut, which is the fastest method but not all switches support it.

Forum users consistently prefer desktop controllers for convenience. The wired connection means no batteries to replace and no signal interference. If you switch frequently throughout the day, a desktop controller saves time compared to reaching for a button on the unit.

Cables Included

This is where budget switches vary wildly. The UGREEN models include HDMI and USB cables in the box, which can save you a significant amount. The BINZET includes only a USB cable, meaning you need to buy HDMI cables separately. Always check what is included before comparing prices, as the cost of quality display cables can shift the value equation.

macOS Compatibility Notes

If you are mixing Mac and Windows computers, there are additional considerations. macOS handles display disconnections differently than Windows, and the lack of EDID emulation causes more disruptive behavior on Macs. Windows may rearrange windows, but macOS can reset display preferences entirely. The M1 and M2 MacBooks have specific USB-C display limitations that some KVMs handle poorly.

For mixed Mac and Windows setups, I recommend switches with EDID emulation like the Hearvo or GREATHTEK. The USB-C connection on newer Macs works with most HDMI KVMs through a USB-C to HDMI adapter, but test your specific configuration early to avoid compatibility surprises.

Frequently Asked Questions

Wrapping Up

Finding the best KVM switches for dual computers in 2026 comes down to knowing what your setup demands. If you need dual monitors with hybrid port support and maximum stability, the Unitek HDMI DisplayPort KVM Switch is the clear winner. For gamers who want triple monitors at 240Hz, the UGREEN 8K premium model is unmatched. And for budget-conscious users who still want EDID emulation, the Hearvo single or dual monitor switches deliver outstanding value.

The feature that matters most across all price points is EDID emulation. It prevents the window rearrangement frustration that dominates forum complaints and negative reviews. Every switch I recommended with EDID support earned consistently higher satisfaction ratings than those without it. Pick the model that matches your monitor configuration, port requirements, and budget, and you will transform how you work across two computers.