Choosing the best graphics card for upgrading your PC can be difficult. Too much power and the graphics-processing unit (GPU) sits idle in a game, waiting for the CPU to finish whatever it’s doing. Too little power and the CPU waits for the GPU to wrap up its tasks. In either case your game won’t look or play as you want it to.

In the past few months ATI and nVidia have both rolled out second-gen DirectX 11.0-compliant graphics cards. These revised GPUs offer improved performance and more robust feature sets. The mid-range cards are also able to outperform the high-end versions of only a few years ago.

To illustrate just how much graphics technology has improved, we’re upgrading a less-than-cutting-edge Windows 7 PC running an Intel Core 2 Quad Q9650 CPU. Since Intel released its second-gen Core processors, this CPU is average at best. A good mid-range graphics card (£200 or less) is the appropriate fit for it.

Our PC’s system case is a concern. Some graphics cards, such as ATI’s Radeon HD 6900 line-up, can be rather long, and may not fit in certain cases. Our desktop’s chassis lacks internal depth, so a mid-range card becomes a matter of necessity.

You’ll also need to consider the power supply. If you’re already running a powerful 900W-rated unit, you can upgrade to just about any graphics card you desire. But if you’re running a less formidable 500W or 600W supply, for example, your options will be more limited. Some high-end graphics cards consume significant amounts of current at startup as well as under load, which can overstress a modest unit.

However, even within such constraints, your graphics card choices are numerous. We tend to opt for newer mid-range cards, which can offer impressive performance on single monitors running at a 1920x1080-pixel resolution. At prices closer to £150, an ATI Radeon HD 6870 would be a good choice. Above £200, an nVidia GeForce GTX 560 Ti would suit.

We’re upgrading from a GTX 260 to a GTX 560 Ti DirectCU II. This card costs around £200, but is stronger and should substantially improve performance.

Upgrade Advisor

Fit a new graphics card

Step 1. Before you buy a graphics card, make sure that your machine’s power supply unit (PSU) is up to the task. Our sample PC has a robust 750W Corsair PSU, which should be sufficient. Check the manufacturer’s specifications for minimum power requirements before you take the plunge.

Step 2. Ensure that the system case has enough room for the new card. Graphics cards have become longer over the years, and the space in older cases may be a little tight.

Continues >>

Step 3. Download the latest driver for the new graphics card, but don’t install it yet.

Step 4. Uninstall the older graphics drivers. Even if you’re installing a graphics-processing unit (GPU) of the same brand as before, removing the older drivers prior to installing the new card is a good idea.

Step 5. Power down the system.

Upgrade Advisor

Step 6. Carefully disconnect any power connectors from the old graphics card. Also undo and remove the screws that attach the connector bracket to the case.

Graphics upgrade 1

Graphics upgrade 2

Carefully disconnect the power cables from the old card and remove the screws holding it into place

Step 7. Ensure that no clutter (cables or wiring) surrounds the card. Note that large CPU heatsinks can interfere with physical card removal or installation, so you may need to remove this component. Ensure you detach the monitor cable from the old graphics card’s outside connector, too.

Step 8. Most motherboards have a little latch that locks the graphics card securely into its slot. You may find it necessary to hold this latch down while removing the card with your other hand.

Graphics upgrade 3

You might need to hold down a latch with one hand while removing the graphics card with another

Continues >>

Step 9. If there’s limited room inside the case, you might have to pre-attach the power connectors to the new card.

Step 10. Install the new graphics card, first making sure that no small wires are overhanging the PCI Express slot. If the card seems difficult to push down, check to see whether the connector bracket is sliding in properly.

Graphics upgrade 4

Install the new graphics card in the correct slot. Here, the turquoise slot is too small

Step 11. Once the graphics card is firmly in place in your PC, replace the connector-bracket screws.

Step 12. Attach the monitor cable. If you’ve previously been using a VGA cable and your monitor has a digital input (DVI, HDMI or DisplayPort), now is a good opportunity to switch to using a digital input with the right cable.

Upgrade Advisor

Step 13. Double-check to confirm that the graphics card’s power connectors are in place. Additionally, verify that no small wires or cables will interfere with any of the cooling fans.

Graphics upgrade 5

Organising cables makes it easier to access the PC's insides later

Step 14. Power up the PC. If you hear any rattling, it indicates that something is rubbing against the fans; power down and check to make sure that no fans have become blocked.

Step 15. Once the system is powered up and running normally, install the latest drivers for the graphics card. Following a final reboot, your card is ready for use.