So, you want to be a PC gamer huh? Welcome to the Big Leagues! You’re about to enter a whole new ballgame, where amazing graphics are limited by only one factor — the size of your wallet. While PS3 and Xbox 360 fans bicker about which console looks best, the PC continues to blast ahead of the competition, offering ten times the raw performance of either. In our three-part guide, we explain how all this cutting-edge technology works, and today’s article looks at one component of the holy trinity of hardware – the graphics card.

Last week, we took an introductory look at how the CPU, motherboard and memory work when it comes to gaming (click here for a recap ). This week, we’re turning our attention to the most important component of all. Nope, not the mouse: the PC graphics card. The graphics card (also known as a ‘video card’) is the combined heart, soul and mojo of any serious gaming PC. While components such as the CPU and RAM play an important part, the graphics card is the engine that powers your games’ graphical prowess. Everything that ‘moves’ in a game’s world — from shifting shadows to hulking aliens — is rendered by your PC’s graphics card, after its been fed the necessary data by the CPU. The more powerful the graphics card, the sexier your games will appear. In addition to making games look better, a decent graphics card will also let you to play games at higher frame-rates (click here for a detailed explanation of computer frame-rates), which translates to a smoother gaming experience. In short, it’s like Sex Panther from Anchorman – except it really works.

Of course, it’s still possible to play the latest games on a mid-range graphics card – it all depends on how detailed and lifelike you want your games to be. (Unlike consoles, most PC games allow the player to adjust graphical settings to match what their machine can handle.) Let’s take a look at the basics.

What makes ‘er tick?

An AMD GPU, about the size of a stamp.

The main component in a graphics card is the graphics processing unit or ‘GPU’ (not to be confused with CPU, PSU or ( STFU). The GPU is similar to the CPU (explained in last week’s article, but is tailor made to display computer graphics, whereas the CPU can do a variety of tasks. The most powerful graphics cards come with two GPUs on the same card for a significant boost in power, such as NVIDIA’s GeForce GTX 590 and AMD’s Radeon HD 6970. Finding out which GPU a graphics card uses can be a very confusing affair, as they use a variety of code names for identification. However, the higher the product number of the graphics card, the faster the GPU. For example, a GeForce GTX 580 has a faster GPU than the GTX 570, which in turn has a faster GPU than the GTX 560. There are a couple of exceptions to this rule, but usually the higher the product number, the faster the GPU.

Graphics cards also have their own dedicated memory built into them, and — generally speaking — the more memory the better. However, the amount of memory is nowhere near as important as the type of GPU used on the graphics card. However, video card manufacturers often place huge amounts of memory on the graphics card simply for marketing reasons – buyers tend to think higher numbers are better. The fastest single GPU video card on the market only has 1.5GB of memory, but there are cards that include a whopping 3GB. Most current-generation gaming cards will come with at least 1GB of memory, which is enough to play the latest games at reasonable settings.

SLI/CrossFire

Two AMD Radeons in CrossFire mode.

If you’re really serious about gaming, it’s possible to put more than one graphics cards inside your computer. This basically lets multiple GPUs work on tasks simultaneously via a connecting bridge, with up to four cards crammed into one PC.

NVIDIA calls this technology ‘SLI’ (Scalable Link Interface), while AMD goes for the cooler moniker ‘CrossFire’, but they basically achieve the same thing. To run SLI or CrossFire you’ll need multiple video cards that are identical – it’s possible to run with different versions of cards, but trust us, it’s not worth the pain involved. You’ll also need a motherboard that supports either SLI or CrossFire, and most modern gaming motherboards support both. Running two video cards requires a significant amount of power, so you’ll also need to beef up your computer’s power supply unit – a high quality 850W PSU you should to the job nicely. All this power generates plenty of heat, so you’ll have to use a PC case that has plenty of ventilation. To make matters even worse, most games don’t support CrossFire or SLI at launch; it takes a driver update from NVIDIA or AMD before dual GPUs start working properly. Thankfully drivers for big name games like Battlefield 3 are usually released immediately, but if you like playing niche games you may have to wait several months before working dual GPU drivers are released. If you’re planning to join four high-end gaming cards, would you mind spotting us some money? You can obviously afford it.

NVIDIA vs. AMD
The two major players in the graphics card market are NVIDIA and AMD (formerly ATI). These companies produce the ‘GeForce’ and ‘Radeon’ line of graphics cards respectively. NVIDIA is currently touting its GeForce GTX 500 Series, while AMD has the Radeon HD 6000 range. Most gamers are fiercely loyal to either NVIDIA or AMD and will often go to great lengths to demonise their rival. It’s like a Montague and Capulet thing (or if you prefer less Shakespearean analogies, DC vs. Marvel). In short, you’re supposed to choose a side and stick with it.

There was a time when NVIDIA was the only choice for serious gamers, but in recent years this has begun to change. AMD Radeon cards are now able to hold their own against their GeForce equivalents, and they’re usually cheaper into the bargain. That said, NVIDIA is still considered king when it comes to ultra high-end offerings: a top-of-the-range GeForce card can still run rings around everything else. (Note: Remember what we said about die-hard loyalists? Keep an eye out for outraged rebuttals from AMD fans in the comments section below.)

Which card?

The ASUS GTX 580 – one of the fastest graphics cards on the market.

The current top-dogs in the NVIDIA and AMD camps are the GeForce GTX 590 and Radeon HD 6990 respectively (if you want a truly stupid fast PC, go for dual GTX 580s like I did – gloating Ed) As you’d expect, these cards cost an arm and a leg, plus interest. If you’re a hardcore gaming enthusiast, the hit on your wallet will be worth it. But for everyone else, we recommend plumping for a high-end card from the previous generation. (Examples include the GeForce GTX 480 and Radeon HD 5870.) These cards can play the latest games at decent settings, but they’ve gone down in price significantly. One thing to remember is that your graphics card is but one element of the holy trinity of hardware; you’ll need an appropriate CPU and 4GB of memory to back it up. If you’re buying a high-end graphics card, a low-end CPU will hold it back from its full potential. Likewise, a super fast CPU will be held back by a low-end graphics card. If you’re running an expensive graphics card, make sure you’re also running a suitably powerful CPU, and vice versa.

Before you choose a graphics card, make sure it’s compatible with your motherboard and power supply unit (PSU). Unless you have an embarrassingly ancient motherboard, it will likely have one or more PCI-Express slots (PCIe) slots, which your graphics card connects to. However, most high-end cards require additional power, which is supplied by your computer’s PSU (AKA the bit that plugs into the wall). You need to check how many six- and eight-pin plugs the your graphics card has, and ensure your PSU has the necessary number of plugs. Luckily there are cheap plug adaptor that cost just a couple of bucks, which can convert different PSU power plugs into the right kind for your graphics card.