Last night, I replaced my graphics card. The previous one was a bit outdated, but more importantly, it had developed an interesting fault whereby in 3D mode (i.e. gaming), image construction was tending to fail badly, especially when looking long distances across the landscape of Azeroth. It would tend to degrade over a session, though dropping to minimum view distances ameliorated the problem somewhat. However, when fighting a mob, having large chunks of the view degrade into large coloured triangles converging onto perspective points was not useful.

Switching it to the other PCI-e slot didn't solve the problem.

The fan was fine.

Updated drivers failed to fix it.

So a new card seemed to be the solution. Given that it was probably time to go for a more capable card than the Radeon 1950 Pro I got last time, but didn't want to have to change anything else, an ASUS HD4850 1GB seemed to fit the bill. It's just 9" long, which means I can get it into the case (I have one free slot in the drive cage behind it, into which the tip of the card protrudes - anything longer than 9" is out as a result.) It uses only one 6-pin additional power connector, so doesn't need a PSU upgrade.

My 3DMark score just doubled, which considering the mobo didn't change is not bad. And I'm now wandering round Northrend with all graphic settings set to max, with a decent framerate, going ohh, ahh at the view. I can now see the real difference between the 'classic' landscapes and the new Lych King ones.