Graphics cards are so important - theyproducing the biggest performance variable in a desktop PC.

We've capped the pricing at £150.If you only upgrade one component in your PC, make it your graphics card. It's going to have the most dramatic effect to your video playback, gaming frame rates and graphical quality.

Before we delve into the group test, there are a few things to mention. If you're sitting on a powerful last-gen GPU, you're faced with quandary: buy another of my existing card for a cheap SLI/CrossFire setup, or start again with a new single GPU.

In general, we'd recommend the newer single card, but it does depend on what you've got to work with in your existing rig.

Grpahics cards

Nvidia's GTX 280s have retained their value sickeningly well, yet can't hack DirectX 11 tech like tessellation, which makes them a horrible choice for SLI. More recent AMD Radeon HD 5 series cards might be a more viable option, though.

There's another reason to drop a little extra dollar on graphics: integrated graphics solutions are getting better. Intel's HD Graphics 3000 engine is pretty good, and AMD's Llano APUs are fantastic. If you buy a low-end card like an HD 4 series card, you're not really getting anything better than integrated graphics than may already be at your fingertips. So which card should you back? Read on…

Cards on test

Sapphire HD 5670 Ultimate - £75
Sapphire HD 6670 Ultimate - £80
Palit GTS 450 - £81
XFX HD 5770 - £81
Sapphire HD 6770 VaporX - £82
EVGA GTX 550 Ti - £98
XFX HD 6850 - £118
Gigabyte GTX 560 - £148