Hi guys, first post here.

I've built many computers, but this is the first I've really tried to overclock. I've got an XBX2, E6600 and 2x1GB G.Skill "HZ" DDR2-800 memory.

Right now, I'm at strap (ref freq)=266, mem speed=800, fsb=333 (2.99 GHz). All voltages are stock. System is stable.

Not a particularly interesting OC (definitely not xtreme!), but I'm waiting until I receive my Thermalright Ultra-120 before I push it any higher (using the retail heatsink/fan right now; load temps are in the low 60s).

Anyway, here's what's interesting: while trying to achieve this OC, I first pushed my mem speed down to 667. The system was stable, except for my Promise SATA II TX4 150 PCI SATA card. This card has four drives attached to it; with the memory speed set at 667, the card would only detect three of the four drives. I rebooted many times, each time shutting down completely and double-checking that my cables were properly seated. No luck.

But when I moved the memory back to 800, the SATA card correctly detected all drives!

Anyone have any idea what might cause this? I plan to try and push the CPU higher, but will surely need the ability to change my memory speed.

As a side note: my goal is to have the max stable OC without increasing any voltages (for heat, silence and longevity of my hardware). I'm not going for any records, just want to get the most value out of my hardware.

One more note: you may be asking, why use the Promise SATA card when there's a perfectly good Marvell SATA chip built in to the XBX2? Well, this system runs Linux exclusively, and (at this time), the Promise drivers are more stable/mature than the Marvell ones.

Thanks!