Here's a strange one. Purchased a 256 stick to upgrade from 128. Board can take upto 512 (so it says)
On boot up showed 2 x 128, swopped them round, tried the 256 on its own - wouldn't recognise 256. Returned to shop who tested it as 256. They suggested that maybe my board would only take 2 x 128 (doubted this but hey I'm no expert). They changed the 256 for a 128 (and gave me a refund) now its showing as 64.
Any ideas? Is it a fault on the dimm slots or motherboard.