When Alex came over, she bought over a couple of 1Gb sticks of PC 6400 DDR2 RAM. I ran some benchmarks before installing the new memory, and then afterwards a couple of times. In terms of pure memory performance, I saw an increase of around 30%, over the original PC4300, and when looking at the overall performance for games and work applications (such as Photoshop and other memory intensive applications, such as video editing) there was still an improvement of around 10%.
My motherboard can only actually drive the memory at up to PC5300 speeds, but the over-specification should be beneficial for two reasons - 1) I should be able to squeeze some more aggressive timing settings out of the over-specced RAM 2) The next time I upgrade my motherboard, I stand a chance of being able to use the same RAM without any performance dip.
One of the problems with obtaining cheap ram is knowing which are cracking deals, and which are simply cheaper due to their lower quality components. It was good to see OEM PC World know their stuff, as they clearly state on the linked page that the quality of a memory stick is NOT down to the brand name attached, but the actual manufacturer of the individual memory chips found on the stick.
Anyway, their prices were pretty competitive, and if you are not sure just which type and spec memory your motherboard supports, the site can detect your motherboard make and model, and then suggest appropriate memory sticks. I ran the test, and the results match up with my previous manual investigations. However, if you do decide to over spec your system, don’t forget the test results are for people who wish to save the most amount of money, so you will need to look around the site a little if you find yourself in this position.