I have just recently encountered a problem with my P5E motherboard. I have had my memory sticks located in A1,A2 slots in dual channel working fine (since spring of '08) until now. I was having problems posting and couldn't even get to BIOS and got a CMOS checksum error once before this happened. Well I've replaced the battery on the motherboard, and even updated BIOS. I have found that any time I put a memory stick in A2 or B2 my computer won't post, it comes on with the fans on high and just sits there with no video on screen. I have also tried manually adjusting timings and voltage but to no avail. (which I've never messed with before) I've also ran Memtest86 and the sticks are fine. I'm out of ideas and think the board need to be fixed.
Setup: ASUS P5E LGA 775 Intel X38 ATX Intel Motherboard
OCZ GameXStream OCZ700GXSSLI 700W ATX12V SLI Certified CrossFire Ready Active PFC Power Supply
G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 1000 (PC2 8000) Dual Channel Kit Desktop Memory Model F2-8000CL5D-4GBPQ
EVGA 512-P3-N841-AR GeForce 8800GTS (G92) 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card
Western Digital Raptor X WD1500AHFD 150GB 10000 RPM SATA 1.5Gb/s 3.5" Hard Drive