I've had my i7 overclocked at 4ghz stable for about 3 years now. About a year-ish ago, I switched my OS over to 2 SSDs in RAID 0 configuration. During that process, I had to completely reinstall my OS. Ever since then my overclock has been less-than-steady. This makes no sense because I OC'd from BIOS, NOT anything in the OS. I would think that would take the OS completely out of the equation.
The main problem I have is with Sleeping the PC. 2 distinct problems have arisen:
1) When sleep command is issued, screen turns off, PC power indicator light blinks as normal when in sleep state, but power is NOT shut off. Fans still spin, presumably power is still going to SDDs/HDDs, lights are still on. The system is not able to be awakened from this state (at least not via my Bluetooth peripherals). A hard reset is required.
2) When sleep command is issued, screen turns off but hard drive light remains illuminated and power indicator light does NOT indicate sleep status was achieved. System is unresponsive and says like this until hard reset is issued.
Problem number 1 is often then accompanied by several "overclock failed!" notices upon restart. After several cycles of this, the system will start and function normally. This ranges in frequency between 1 in 15ish sleep commands, and can happen as infrequently as once every 2 months. The "overclock failed!" notice never happens after problem 2.
It seems like the longer the PC has gone without a full restart, the more likely one of these issues is to arise. I don't know if that's true or just placebo on my part. I never had any issue with my OC for 2 years - under any circumstances - until I reinstalled my OS. I don't get it.
Intel I7 OC'd @ 4ghz (OC via BIOS)
2 OCZ Vertex SSD RAID 0 (system drive) + 2 HDD (Data, Backup + Pagefile)
ASUS P6T Mobo
Nvidia GTX 560
800 Watt PSU
W7 Home Premium 32 bit (power settings set to NOT suspend power to drives b/c of SSDs)