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.
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.
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.
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.
Anti-aliasing
One of the biggest strengths of PC graphics card is their ability to enable anti-aliasing, a feature that many console games lack - the 360 and PS3 simply don't have the horsepower necessary. Yet many PC gamers don't understand what this term means, and how to enable this feature on their video card.
In the simplest of terms, aliasing is a problem that results from the fact our computer displays are made up of dots. When these displays draw a line that isn't perfectly horizontal or vertical, due to the dots, it can appear wonky, with noticeable jagged edges, which is why aliasing is often referred to as "the jaggies". Anti-aliasing smooths these edges out, so that the line looks perfectly straight, and it's more noticeable the bigger your screen is. There are different levels of anti-aliasing, 8X looks better than 4X, which looks better than 2X, and there are also many different types of anti-aliasing, which all use different approaches to solve the same problem.
While most PC games include an option in the graphics menu to enable anti-aliasing, NVIDIA and AMD both offer additional levels of anti-aliasing. The faster your video card, the better the anti-aliasing can be. Simply right click on your desktop, and you'll see NVIDIA's Control Panel or AMD's Catalyst Control option – select this, and under the 3D settings you'll see an option for overriding your game's anti-aliasing. Select this, and then select the level of anti-aliasing you want to try, bearing in mind that even the fastest video cards can be slowed down if anti-aliasing is set to high. Fire up your favourite game and be amazed at how much better it looks! We'll have a more detailed tutorial in the near future about how to get really clever with anti-aliasing using third party software.
NVIDIA's Control Panel
Today's graphics cards are much more powerful than their console cousins, so it's possible to play most console ports with a relatively cheap graphics card. However, if you're running a big screen plasma or projector at high resolution and high levels of anti-aliasing, you'll want the fastest card – or cards – you can afford. Just remember that you need to have a balanced system, as even the fastest video card in the world won't be of any use if it's running with a pocket calculator CPU.
Spy Guy says: Are you an AMD or NVIDIA gamer? Will you be splashing out on a new graphics card for the Battlefield blockbuster?
