The cumulative power of a dual GPU card setup makes sense.
Two is better than one, after all, right?
Now, it’s true that using 2 graphics cards does indeed bring real benefits. However, there are real downsides to this kind of set-up too.
With that said, scroll down below to learn more about the reality of running two graphics cards, and whether it’s worth it or not.
How do Dual Graphics Card Work?
Nvidia SLI and AMD CrossFire are two technologies utilized by the biggest graphics card manufacturers in the world to allow for two graphics cards to work together and share the workload with each other.
In doing so, these technologies would be able to give systems twice the computing power that it needs to handle demanding conditions.
This includes, among others, rendering scenes. The set-up effectively doubles the efficiency by allowing each graphics card to render every other line.
In theory, this should lead to double the performance compared to just having a single graphics card.
Does Having 2 GPUs Increase Performance?
In an ideal world, using multiple graphics cardsshould increase performance. In the real world, things aren’t so simple.
For an increase in performance to be felt, a particular software or game will need to be optimized for such set-ups. This is much easier said than done.
The reason being is that developers will have to put in the work to make sure that their software or game is optimized for SLI or CrossFire.
The main problem with this is that it takes away from time that they could have used to optimize a game or software for single GPU cards.
This is why you see some games or software performing worse for users with an SLI or CrossFire set-up.
Now, while some video game studios and software developers do take the time and resources to optimize their product for both dual- and single-GPU set-ups, there’s just not enough upside for them for this to be an industry standard.
Can You Use Two GPU’s Without SLI or CrossFire?
Yes. It is possible to run two graphics cards without SLI.
Just keep in mind that this kind of set-up is useful only in a very specific scenario — if you’re running multiple monitors.
Sure, it is possible to run more than one monitor using a single graphics card. However, this will severely limit the performance of your graphics card if, let’s say, you’re running a GPU-intensive task, like rendering or playing video games.
Running two graphics cards without using CrossFire or SLI is a good solution to this.
By connecting each monitor to one graphics card, you’ll be able to effectively split the load between both graphics cards. This means that you can render videos or graphics on one monitor and then play a video game on the other.
Some people do this to run multiple instances of the same game or software on one system and output it to separate monitors, as well as keyboard and mouse.
Of course, it should go without saying that you need to have a system that supports such a setup. Your processor, in particular, should be able to handle such kinds of workloads if you plan on doing this.
Now, if you don’t plan on doing this, then you’re just wasting your time and money trying to run a dual graphics card setup.
If you already have an extra lying around though, it should make for a fun and neat experiment.
As far as pure dual GPU card set-ups go, the AMD Radeon Pro Duo is considered the fastest in the world today.
It comes with 8GB of High Bandwidth Memory with as many as 8192 Stream Processing Units. It’s also been fitted with its very own closed-loop liquid cooling system, complete with a 120mm radiator, to keep it cool under load.
Speaking of load, the Radeon Pro Duo requires 3 x 8-in PCI-E power connectors with a maximum TDP of 350w.
Although AMD recommends a power supply with at least 700W, many recommend using a higher wattage power supply for safety.
The AMD Radeon R9 295X2 is basically just two pieces of the R9 290x graphics cards designed as a single graphics card running at a higher frequency.
It has 5632 Steam Processors with 8GB of GDDR5 memory, allowing it to play a vast majority of titles at 1440p and even 4K smoothly.
As the predecessor to the Radeon Pro Duo, the Raden R9 295X2 was one of the first graphics cards to use a water cooling unit.
However, unlike its successor, the Radeon R9 295X uses a hybrid system. It’s composed of a water cooling unit for the graphics cards with a Heatsink Fan responsible for keeping the VRMs cool while under load.
The Radeon R9 295X2 consumes a lot of power. Although it only requires 2 x 8-pin PCI-E power connectors, it’s recommended to use at least an 800W power supply to run it.
But, because it has a maximum power consumption of 500 watts under load, a higher wattage power supply than 800W is almost always recommended.
An older graphics card utilizing DirectX 11.1 technology, the AMD Radeon HD 7990 was a fairly powerful graphics card for its time.
It was also one of the first dual GPU cards to optimize cooling by using multiple fans. It’s fitted with 6GB of GDDR5 memory along with 4096 steam processors.
What makes this dual GPU card unique is that you can still use it in a multi GPU setup. This means that if you have an extra HD7990 lying around, you can effectively use both together to run, technically, 4 graphics cards in unison.
But, doing so will require a lot of power, as, on its own, the Radeon HD 7990 is expected to draw at least 400W of power.
Better gaming performance at higher resolutions: When gaming at higher resolutions like 4K and 8K, the power of a dual GPU shines best and allows you to run games at higher frame rates much more smoothly often at a higher graphics quality.
Upgrade path: Because a dual GPU set-up requires compatible hardware, such as the motherboard, case, power supply, you’re guaranteed to have high-end components in your set-up already that make it easier to facilitate upgrades down the line. At the same time, you won’t be needing to upgrade your graphics card and other hardware components soon as well.
Support for multi-monitor set-ups: A side benefit of having a dual GPU is that it can support multiple display monitors right out of the bat.
Expensive: From the added electricity costs of running a dual graphics cards setup to how expensive a dual GPU card usually is, a dual GPU card set-up can cost you a lot of money the more you use it if it’s not necessarily utilized for whatever workflow you have planned for it.
Issues with driver and compatibility: Not all games are designed by its developers to support dual GPU cards. So, instead of seeing the graphical performance of your set-up improve, some dual GPU cards might even end up performing worse than their single GPU counterparts.
Is Two GPUs Worth It?
The thing is, we’ve only been able to finally utilize multicore processors properly.
It took years, especially in video games, for developers to properly optimize titles to distribute work evenly across multiple cores.
Why did we bring up processors in a discussion for graphics cards? It’s because a single graphics card alone can have dozens if not hundreds of cores.
This means that getting more than one graphics card to work together properly is a headache that most graphics cards manufacturers and developers would prefer not to deal with.