memory related crash

Hi,

I have windows 7 Home Premium 64 bit (retail) running on an intel i3 cpu @ 2.93ghz, corsair SSD, radeon x1950 and an Asus p7p55d-e mobo with Ubuntu installed on a separate hard drive. I put the system together about 4 months ago, have had this issue the whole time..

My problem is that when I have both my 2gb ram sticks installed windows only runs for a few minutes before freezing up completely, leaving me having to reboot. It doesnt matter which slots the ram is in, but if I only have one stick in (either stick, in any slot) it runs fine. Ubuntu on my other hard drive works perfectly fine with both sticks installed.

The two sticks are identical and I have run memory tests for hours at a time and they have never found any errors. It must be a windows thing but I thought the 64 bit version was supposed to be fine with 4gb ram?



Any ideas please??