How to choose a graphics card

If you’re looking to buy or build a new gaming PC, one of the most important questions to ask is, “What graphics card do I need?” It can be a tough choice, with not only various manufacturers to pick from but also various versions of each individual graphics card. How do you upgrade your video card if you’re not even sure which one you should buy?

Choosing a graphics card is all about learning to read the numbers and determining what’s important. Do you need more VRAM or more graphics processing unit (GPU) cores? How important is cooling? What about power draw? These are all the questions we’ll answer (and more) as we break down how to find a GPU that’s right for you.

AMD vs. Nvidia vs. Intel

Nvidia RTX 2080 Super impressions
Riley Young/Digital Trends

When it comes to buying a new graphics card, the two main choices are AMD and Nvidia. These two industry giants have the most powerful cards, and even their budget offerings are designed with gaming at HD resolutions in mind. Intel is mostly known for its integrated or onboard GPUs. Bundled along with its processors, those aren’t really designed for gaming in quite the same way. They can do it, but they’re best suited to independent games and older titles.

That may change in 2020, with Intel set to debut its first dedicated graphics card in decades. Until it does, AMD and Nvidia make the best graphics cards for desktops and laptops.

There are more choices to make than branding when it comes to choosing a graphics card, but AMD and Nvidia do have some distinguishing features that are unique to their hardware. As of late 2020, Nvidia graphics cards are the only ones that support hardware accelerated ray tracing. They also enjoy exclusive support for G-Sync technology and tie in well with GeForce Now. There’s also deep learning super sampling, which has proven itself capable of delivering impressive performance improvements to a limited list of supporting games.

Nvidia also has the most powerful graphics cards available by quite some margin. The flagship RTX 3080 is a 4K behemoth, if you can find one in stock. The RTX 3090 is even more impressive, but at $1,500, it’s a tough sell for most users.

That doesn’t mean AMD is down and out, though. Indeed, its high-end graphics cards are capable and hold an important niche in the market. Its GPUs tend to offer slightly greater value for money in most sectors of the market, though its feature set is arguably weaker. It offers support for Freesync frame syncing (a comparable technology to G-Sync), as well as image sharpening and other visual enhancements, which can make games look better for almost no additional cost in resources.

It doesn’t offer ray tracing or DLSS support, but the former is set to change toward the end of 2020 with the release of AMD’s next-generation graphics cards. AMD teased benchmark numbers for its upcoming RX 6000 GPUs during its Zen 3 reveal in October, and the results were impressive. We’ll know more about performance when AMD fully unveils these GPUs on October 28, but we at least know that they’ll introduce ray tracing to the product line.

Ultimately, when it comes to picking a GPU, it is useful to consider whether your monitor supports Freesync or G-Sync and whether any of the companion features of these companies’ graphics cards can help you. For most, price and performance will be more important considerations.

CUDA cores and streaming processors

Nvidia GPU photo
Jacek Abramowicz/Pixabay

Although CPUs and graphics cards have processor “cores” at their heart, their tasks are different, so the number of them is different, too. CPUs have to be powerful, general-purpose machines, while GPUs are designed with masses of parallel — yet simple — calculations at any one time. That’s why CPUs have a handful of cores and GPUs have hundreds or thousands.

More is usually better, though there are other factors at play that can mitigate that. A card with slightly fewer cores might have a higher clock speed (more on that later), which can boost its performance even above that of cards with higher core counts — but not typically. That’s why individual reviews of graphics cards and head-to-head comparisons are so important.

In our test of the 2080 Ti and 2080, the higher-end card was able to output over 100 frames per second in Battlefield 1 at 4K with all settings at Ultra, where the 2080 only managed 74 fps on average. The more midrange AMD RX 5700 and 5700 XT delivered similar sort of frame rates at 1440p in Battlefield V, though fell to just under 60 fps each at 4K.

Called CUDA cores in the case of Nvidia’s GPUs and stream processors on AMD’s cards, GPU cores are designed a little differently depending on the GPU architecture. That makes AMD and Nvidia’s core counts not particularly comparable, at least not purely on a number basis.

Within each product line, however, you can make comparisons. The RTX 3080, for example, comes with 8,704 CUDA cores, while the RTX 3090 has 10,496. By comparison, the 2080 Ti has around 4,300 CUDA cores, half of what the 3080 has. These are two different generations of GPU, however, and just because the 3080 has double the CUDA cores, that doesn’t mean it has double the performance.

Turing CUDA cores — the ones on 20-series GPUs — can handle an integer and floating point calculation simultaneously per clock cycle (FP32 + INT), while Ampere CUDA cores — the ones on 30-series GPUs — can handle double floating point calculations, too (FP32 + FP32). So, although there is a huge theoretical performance increase, the difference in core workload doesn’t make the two generations of GPUs directly comparable.

Nvidia cards now have RT and Tensor cores, too. The RT cores are simple enough, handling hardware ray-tracing with Nvidia’s RTX-branded GPUs. Tensor cores are a little more involved. Nvidia introduced its Tensor cores with Volta, but it wasn’t until Turing — the generation of GPUs including the RTX 2080 — that consumers were able to buy into the new tech. Nvidia has continued to expand on Tensor cores with its Ampere architecture, featured in the RTX 3090 and 3080.

Tensor cores accelerate floating point and integer calculations, but they’re not built equally. First-gen cores on Volta simply handle deep learning with FP16, while second-gen cores support FP32 to FP 16, as well as INT8 and INT4. With the most recent third-gen cores, featured on RTX 30-series GPUs, Nvidia introduced Tensor Float 32, which functions identically to FP32 while speeding up artificial intelligence (A.I.) workloads by up to 20 times.

For these cores, it’s not about the number of them, but rather what generation they’re from. Between RTX 20-series and 30-series GPUs, 30-series cards are better equipped here. We imagine it’ll get more complex as time goes on — Tensor cores aren’t going anywhere — so if you can afford a more recent Nvidia GPU, it’s usually best to stick with one.

VRAM

AMD Radeon RX 5700 and 5700 XT review
Dan Baker/Digital Trends

Just as every PC needs system memory, every graphics card needs its own dedicated memory, typically called video RAM (VRAM) — though that’s a somewhat outdated term that’s been repurposed for its modern, colloquial use. Most commonly, you’ll see memory listed in gigabytes of GDDR followed by a number, designating its generation. Recent GPUs range anywhere from 4GB of GDDR4 to 24GB of GDDR6X, though there are also existing graphics cards with GDRR5. Another memory type, called high bandwidth memory (HBM, HBM2, or 2e), offers higher performance at a greater cost and heat output.

VRAM is an important measure of a graphics card’s performance, though to a lesser extent than core counts. It affects the amount of information that the card can cache ready for processing, which makes it vital for high-resolution textures and other in-game details. If you plan to play medium settings at 1080p, then 4GB of VRAM is more than enough.

If you want to play with higher resolution textures and at higher resolutions, 8GB of VRAM gives you a lot more headroom, and it’s far more future proof — perfect for when next-generation console games start to make the leap to PC. Anything beyond 8GB is reserved for the most high-end of cards and is only really necessary if you’re looking to play or video edit at 4K or higher resolutions.

GPU and memory clock speed

The other piece in the GPU performance puzzle is clock speed of both the cores and memory. This is how many complete calculation cycles the card can make every second, and it’s where any gap in core or memory count can be closed, in some cases significantly. It’s also where those looking to overclock their graphics card have the biggest impact.

Clock speed is typically listed in two measures: Base Clock and boost clock. The former is the lowest clock speed the card should run at, while the boost clock is what it will try to run at when it’s heavily taxed. However, thermal and power demands may not allow it to reach that clock often or for extended periods. For this reason, AMD cards also specify a Game Clock, which is more representative of the typical clock speed you can expect to reach while gaming.

A good example of how clock speed can make a difference is with the RTX 2080 Super and 2080 Ti. Where the 2080 Ti has almost 50% more cores than the 2080 Super, it’s only 10% to 30% slower, depending on the game. That’s mostly due to the 300MHz+ higher clock speed most 2080 Supers have over the 2080 Ti.

Faster memory helps it, too. Memory performance is all about bandwidth, which is calculated by combining the speed of the memory with its total amount. The faster GDDR6X of the RTX 3080 helps improve its overall bandwidth beyond the RTX 2080 and RTX 2080 Ti by around 20%. There is a ceiling of usefulness, however, with cards like the AMD Radeon VII offering enormous bandwidth but lower gaming performance than a card like the 3080.

When it comes to buying a graphics card, clock speeds should mostly be considered after you have picked a model. Some GPU models feature factory overclocks that can raise performance by a few percentage points over the competition. If good cooling is present, it can be significant.

Cooling and power

A card is only as powerful as its cooling and power draw allow. If you don’t keep a card within safe operating temperatures, it will throttle its clock speed, and that can mean significantly worse performance. It can also lead to higher noise levels as the fans spin faster to try to cool it. Although coolers vary massively from card to card and manufacturer to manufacturer, a good rule of thumb is that those with larger heatsinks and more and larger fans tend to be better cooled. That means they run quieter and often faster.

That can also open up room for overclocking if that interests you. Aftermarket cooling solutions, like bigger heatsinks and water cooling in extreme cases, can make cards run even quieter and cooler. Note that it is much more complicated to change a cooler on a GPU than it is on a CPU.

If you play in headphones, low noise cooling may not be as much of a concern, but it’s still something worth considering when building or buying your PC.

As for power, focus on whether your PSU has enough wattage to support your new card. RealHardTechX has a great chart to find that out. You also need to make sure that your PSU has the right cables for the card you’re planning to buy. There are adapters that can do the job, but they aren’t as stable, and if you need to use one, it’s a good sign your PSU is not up to the task.

If you need a new PSU, these are our favorites.

How much should you spend on a graphics card?

With everything else considered, budget could be the most important factor. How much should you actually spend on a GPU? This is different for everyone, dependent on how you plan to use it and what your budget is. That said, here are some generalizations:

  • For entry-level, independent gaming and older games, onboard graphics may suffice. Otherwise, anywhere up to $130 on a dedicated graphics card will give you slightly better frame rates and detail settings.
  • For solid 60+ fps 1080p gaming in e-sports games and older AAA games, expect to spend around $200.
  • For modern AAA games at 1080p or 1440p everywhere else, you’ll likely need to spend closer to $300.
  • 60+ fps at 1440p in any game or entry-level ray tracing in supporting games will cost you $400 to $500.
  • 4K gaming, or the most extreme of gaming systems, can cost as much as you’re willing to spend, but somewhere between $500 and $1,000 is likely.

What about onboard graphics?

Both Intel and AMD make CPUs that include graphics cores on the same chip, typically referred to as integrated graphics processors (IGP) or onboard graphics. They are far weaker than dedicated graphics cards and typically only provide base-level performance for low-resolution and detail gaming. However, there are some that are better than others.

Many current-generation Intel CPUs include UHD 600-series graphics, which make certain low-end games just about playable at low settings. In our testing, we found the UHD 620 able to play games like World of Warcraft and Battlefield 4 at low settings at 768p resolution, but it didn’t break 60 fps, and 1080p performance was significantly lower — barely playable.

Eleventh-generation graphics, found on Intel’s 10th-generation Ice Lake processors, are much more capable. CPUs equipped with that technology are able to play games like CS:GO at lower settings at 1080p. Anandtech’s testing found that a 64 execution unit GPU onboard the Core i7-1065G7 in a Dell XPS 13 managed over 43 fps in DotA 2 at enthusiast settings at 1080p resolution. We found it a viable chip for playing Fortnite at 720p and 1080p, too.

Intel’s 11th-generation Tiger Lake processors are even more capable. Although a far cry from a dedicated GPU, our Tiger Lake test machine was able to hit 51 fps in Battlefield V and 45 fps in Civilization VI at 1080p with medium settings. The fact that we were able to even dream of 60 fps in Battlefield V on integrated graphics was astounding.

AMD’s onboard Vega graphics are more comparable to Ice Lake’s 11th-gen chips, with the higher-end variants offering some surprisingly capable entry-level gaming ability. In our test of the ThinkPad E495 in 2019, we found the Ryzen 7 3700U, with its Vega 10 graphics, more than a match for Half-Life 2 and Diablo 3.

The more recent Ryzen 4000G processors have onboard graphics, too, and they’re impressive. According to some benchmarks, the flagship Ryzen 7 Pro 4750G is able to match current-gen consoles in Assassin’s Creed Odyssey, maintaining above 30 fps at 1080p. The Ryzen 5 4650G and Ryzen 3 4350G aren’t as capable, though they’re still able to maintain framerates well above 60 fps in e-sports titles like League of Legends and Rainbow Six: Siege. 

As passable as these gaming experiences are, though, you’ll find a much richer, smoother experience with higher detail support and higher frame rates on a dedicated graphics card.

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