As title, I ran Memtest86 (the bootable floppy version) to test my 2x512MB Geil Ultra DDR400. I'm on an NF7-S 2.0, with an XP-M which for Memtest purposes I ran at 200x10 (and at default VCore) as I wanted to test the RAM on its default FSB of 200MHz. To test I would boot up Memtest86 and look Test 5. First I tested with VDIMM at 2.6V (default) and the RAM at 2.5-7-7-11. On the first run the computer froze midway through the 3rd pass. Memtest86 didn't report any errors, it just froze. On the second run it did 5 passes with no problem. Then I ran the RAM at 2-4-4-8 (its default timings), with VDIMM at 2.9 (the maximum that RAM is supposed to be rated at), and chipset voltage at 1.8V (achievable by dropping chipset voltage to 1.4 - my board is one of the buggy NF7s which does that). I got hundreds of errors starting 98% of the way through the very 1st pass. Then I dropped VDIMM back at 2.6V, keeping the same timings. Midway through the first pass the computer froze again. I ran it again, "dropping" the NB voltage to default, and it did 6 passes with no problem. Is it RMA time?