The GPU (Graphics Processing Unit) is one of the most important components of any computer, as it accelerates the rendering of 3D and 2D graphics in real-time.
Users with a spare graphics card or a big budget might wonder if you can put two GPUs in the same computer. So, can you use two GPUs on the same computer?
Yes, you can use two GPUs on the same computer. However, there are certain things you need to keep in mind. For example, the GPUs need to be compatible with one another, your motherboard needs to be able to support two GPUs both spatially and compatibility-wise, and you need a PSU that can provide enough power for two GPUs.
There are a lot of things to think about before trying to use two GPUs with the same computer. Before ordering an extra GPU, consider the question in the resource below, and how they may apply to you.
Can You Use Two GPUs On the Same Computer?
You can, as I mentioned before, use two graphics cards on one computer at the same time. That’s not a problem. The crux, however, lies in making them work together.
You can certainly do it. Just keep reading to find out what you need to have in mind before installing double GPUs on your computer.
Of course, the benefits of running a dual GPU setup are vast. If you do it properly, you’ll get more performance out of your computer. This will translate into more FPS in games and higher resolutions.
It’ll cost you a bunch of money, which I suppose is the downside of the dual GPU setup. Also, you need to make sure that your computer has ticked the boxes when it comes to running two GPUs at the same time.
A word of warning beforehand: there’s a well-known bug with SLI/CrossFire setups that will cause something called micro stuttering when playing games. The stuttering doesn’t mean that you’ve done anything wrong or that your computer can’t handle a game, it’s just something that’s relatively common with two GPUs, especially on low framerates.
What Do You Need In Order to Use Two GPUs at Once?
There are a bunch of things that you need to cross off the list, so to speak, to be able to properly utilize two GPUs together.
First of all, make sure that your motherboard has the necessary PCIe slots. Ideally, that would be two x16 PCIe slots. If your motherboard has one x16 and one x8, that works too. As I mentioned earlier, these are the slots where your GPUs will be seated.
Ideally, you’d want two GPUs of the same version (for example, two different GeForce RTX 2080). This way, you can run them with SLI / CrossFire (depending on what brand of GPU you have: SLI is for Nvidia cards, and CrossFire is for AMD).
There are lists available online of all SLI / CrossFire compatible GPUs, and if you want to check yours without looking that up, you can check for an SLI / CrossFire sticker on the card itself.
Next, you must make sure that your PSU can supply enough power to both of your GPUs. If it can’t do that, then your GPUs won’t get the power they need, and that can cause damage to the cards.
After you’ve ticked all of those boxes, you need to make sure that your chassis is big enough to support both GPUs. Two of them can easily take up too much space which means that they simply can’t fit.
They need to have good space to be able to breathe well inside the computer. This is very important, especially since two GPUs generate more heat than one. Good cooling is required.
Before investing in two, or an additional, GPU, make sure that you have a CPU that’s at least okay. If you have an old CPU, this can bottleneck the two GPUs to the point that it’s not worth having them in the first place.
Finally, if you’re going to play old games, they might not support two GPUs, and will as a result only run one. That’s why you should make sure that the games you plan on playing actually support the use of two GPUs. Most modern games support dual GPU setups, however.
How Do You Use Two GPUs In the Same PC?
If you have checked all of the boxes in the text above, let’s go through how you actually run two GPUs on your computer.
First of all, buy an SLI / CrossFire bridge connector. This will let your two GPUs communicate in a more efficient manner, as they will bypass the CPU.
After you have one of those, connect your two GPUs to the previously discussed PCIe slots and then connect your GPUs with the bridge connector. In general, the x16 slot that you want to use is the top PCIe slot. The x8 slot that you probably have for your other GPU is in general the third slot from the top.
If you have questions or concerns about this, check your motherboard user manual. They usually do a very good job illustrating the slots. After you’ve installed your GPUs, you need to download drivers for them.
To do that, go here (or here for AMD drivers). Then, download the software. You have now downloaded the Nvidia GeForce Experience / AMD Adrenalyn, which is an easy-to-use interface that is meant to update drivers for you automatically, and also provides you with a control panel.
Install the software on your computer, and enable automatic driver updates if asked. When you’ve installed the software, right-click the desktop. You should see an option to go into either the AMD AMD Radeon Software or Nvidia Control Panel.
For the Nvidia Control Panel, follow the steps below.
- When you have entered the control panel, click on Configure SLI, Surround, PhysX
- In the new window, click on Maximize 3D performance if it’s not checked, or Span displays with surround if you have two monitors
- Click Apply in the lower right corner
For the AMD Radeon Software, follow the steps below.
- Right-click your desktop and click on AMD Radeon Software
- Click the cogwheel at the top-right of the menu
- Click Advanced
- Toggle Enabled under AMD CrossFire
- Click OK when asked if you are sure
When you enable CrossFire / SLI, your screen will either blink or go blank for a couple of seconds. This is completely normal, just have patience and wait for it to activate the configuration.
What Do You Need to Consider When Using Two GPUs?
Before buying an additional GPU (or two new ones), consider the price first. If buying an additional, identical, GPU is cheaper than buying a brand-new one, then running two GPUs might be worth it.
Of course, this is only if your computer already ticks the boxes that two GPUs require. If you need to switch motherboards for it, it might not be worth it at all.
However, if you need to upgrade your PSU for it, it might be. It all depends on your situation. So, what do you need to consider exactly? Well, I mentioned a lot of them previously but here they are:
- Consider the space in your chassis. There needs to be room for two GPUs + extra room.
- Compare your PSU to the power requirements of the two GPUs that you plan on having.
- Consider the games you are going to play. Some games do not support SLI / CrossFire setups.
- Consider if it’s worth it, period. A lot of the PC and gaming industry is moving away from SLI and it might not be supported at all in the future.
- Make sure that two GPUs are better than one of the same price as the two.
- Consider noise: two GPUs provide more heat and as a result more noise, than a single GPU.
That about sums it up. In general, you need to make a researched decision on whether or not you want to invest in a double GPU setup. When all the practical details such as price an compatability are solved, is it worth it for you, considering the games and programs you want to run on your computer?
What Are the Benefits of Using Two Graphics Cards?
There are things to consider as potential drawbacks, but of course, there are also potential benefits in having two GPUs. Let’s go over them below.
- Depending on your setup, having two GPUs might be cost-effective
- Good for multiple monitor setups
- Can make use of high resolutions such as 4K
- Higher FPS and performance in-game
- Beneficial for video editing softwares (faster rendering, better visual effects)
- You always have a spare GPU in worst case
These are some of the potential benefits to using two graphics cards at the same time, but whether or not it’s good comes down to what you plan on doing, and the other components in your computer.
As I mentioned previously, these benefits won’t be there if your computer can’t power two GPUs, or if the chassis is too small to properly fit two GPUs into your computer.
Can You Use Nvidia and AMD GPUs Together?
Yes, it’s possible but not generally recommended. A lot of users have made it work, so you might be able to make it work as well. One thing to note is that you can’t run either SLI or CrossFire with this sort of setup, so performance might not be optimal.
Some motherboards drop the speed of x16 PCie slots down to x8 when you’re running 2 GPUs, and this plus with the fact that you can’t pair the GPUs of two different brands with a bridge connector to make them communicate directly, will mean a performance decrease. In such cases, it’s probably not worth it.
In multiple monitor setups, using an Nvidia and AMD GPU at the same time can be beneficial. Here, you can assign a monitor to each of your screens and use the best GPU to the monitor where you will be doing the most demanding activities.
You can assign GPUs to monitors. One useful application of this is to assign your primary GPU to the screen you plan on gaming on, while the other GPU takes care of the other. This way, you can play on one screen and do other activities on the other without impacting performance: one GPU will render the game and one will take care of the other monitor that’s showing you the video.
Remember: you can’t get them to use either SLI or CrossFire. They need to be the same brand for this. I wouldn’t recommend buying two new GPUs of different brands for using in the same computer, but if you already have them in your possession, it can work.
Should You Use Two GPUs or Purchase a High-End GPU?
It’s hard to provide a definite answer to this question, but I’ll try to guide you into something that is fitting for you. First of all, if you already have two GPUs lying around, there’s no harm in connecting both to see if you get any performance boosts from it.
Having two cheaper cards can, depending on what cards we’re comparing, give better performance than a single high-end GPU. However, as I mentioned earlier, two GPUs can come with potential issues. For example, it’s fairly common with micro stuttering and pretty loud noise.
Is a potential increase in performance worth this? Personally, I don’t think really think so. If you have the funds for a high-end card, I would recommend that.
This is especially true if you consider the future of GPUs. Support for SLI / CrossFire in both games and systems will decrease of time, and it’s completely possible that it won’t be supported in the future.
If you don’t want to spend as much money, getting two GPUs can be worth it over a high-end GPU. In such a scenario, you already own a decent GPU, and instead of getting rid of it in favor of a high-end GPU, you buy an additional GPU of the same model that you already own. This way, you can save money while still upgrading your performance in a big way.
As you can see, whether or not two GPUs is worth it over a high-end GPU, is entirely up to your preferences and situation.