Although I was able to eliminate it as a possibility late last year, I can now confirm I'm suffering from memory loss. However, the nice people at Crucial will be replacing the faulty component free of charge under their rather good Lifetime Warranty.
I'm quite lucky they have a couple of sticks of the relevant type of memory still in stock, as I originally bought it in November 2001.
I'm quite lucky they have a couple of sticks of the relevant type of memory still in stock, as I originally bought it in November 2001.