I've done a bunch of searching on here and general Google, and haven't found answers, so I apologize if these have been addressed.
Gigabyte GA-Z77X-UP4 TH motherboard
G.SKILL Ripjaws Z Series DDR3 1600 (PC3 12800) F3-12800CL10Q-32GBZL
I had some problems with the CPU (it would fail to boot when enabling virtualization, so I RMA'd both the CPU and MB and have new ones).
Ok, so the two questions.
1. Unlike when I've overclocked in the past (Q6600, Core2Duo's, AMDs), I am not having Prime95 failures, but instead either blue screens in some cases, or if it runs stable for a while, after 1-3 hours will get a windows error of some kind. It could be the Win explorer failed, or Aida64 or Prime95 failed/had an error.
Is this normal with Ivybridge, that instead of getting Prime95 errors, you can get generalized Windows errors?
2. Second, I seem to be closing in a stable overclock. 4.5 GHZ at 1.225 vcore (LLC extreme). I'm confused on how to convert to offset voltage once I find a stable overclock, so I can take advantage of the voltage dropping at idle or low CPU usage.
Regarding #1: After assembling the system did you update the BIOS to latest, reload defaults and then make settings changes, and run MemTest x86+ for 12 hours to verify that your RAM is ok?
I ask this as I had a defective memory module on my previous build (a P45/E8400) that manifested as random BSOD that were very infrequent at first and then 2 months later were occurring constantly. It was very subtle and while windows would crash (usually a display driver) I could run hours of Prime without issue as the CPU was still calculating correctly.
After running Memtest the errors showed up after 3 full test cycles. I RMA'd the memory (Corsair, lifetime warranty) and they replaced the sticks. The system has had no issues for 2 years+.
I just built a new system using 3570K and ASRock Z77 Extreme 4 10 days ago. I ran Memtest for 10 hours for 8 GB (9 full passes). You have 32 GB so you might want to let it run longer.
Regarding #2: I wish I knew what the "reference" voltage is in relation to the offset. On the ASRock I am getting close to 1.3 with the smallest offset of +5mv with a turbo boost of +4mv, yet it overclocks just fine with a lower fixed voltage. This seems to indicate that the "reference" is in the 1.2x range, which seems kind of high. My guess is that each MB manufacturer selects a value within the Intel spec range so I think you will have to determine with testing. Try using the smallest positive offset with the stock multiplier and measure with CPU-Z. Work your way back up to 4.5 and remeasure voltage/temps with each change.