rdave13 has it on the nail. 256Mb per slot and thus a 512Mb maximum is your lot. Noise: 1. Put up with it 2. Lubricate the fan spindle 3. Replace the PSU It has been some time since I did this and I never did find a UK supplier but.. a few drops of graphite penetrating oil on the fan spindle usually does the trick. It can be bought from the USA for 2 or 3 dollars plus the same again for postage.