Originally Posted by TLCH723
My RAM is 3 sets of this
I set the latency to the 9-10-9-28-2N. Since these are 1.5v, I set vdimm to 1.5v.
I already did a memtest so they are fine.
Originally Posted by Kana-Maru
Well you should make sure the system is stable before overclocking RAM or feeling the need to add voltage. Downclock your RAM to a setting that you know is stable with 9-9-9-24 2T [below 1.66v]. Test your system to ensure that it isn't RAM. This will ensure that it isn't your CPU or another setting in the BIOS that needs to be increased\decreased. If your CPU is fine then slowly start to increase your RAM frequency and test.
The RAM and uncore frequencies change with BCLK so to get good RAM timings I found it was easier to do it the other way around: set the cpu multi conservatively so you know the core voltage is definitely OK for the core to be stable and set the RAM multi conservatively so you know the RAM is OK too and first work out what VTT you are going to need for the BCLK and uncore clock you will end up at with your final target overclock.
You want to start by finding max BCLK with a low uncore clock and determine what VTT that requires. Then up the uncore multi and find the VTT you need to get your uncore stable at max BCLK at or above your target uncore frequency.
Once you have VTT for max BCLK at your target uncore frequency you can leave VTT fixed and up the RAM multi and work with BCLK and VDRAM and the RAM timings to find your max RAM frequency.
Start with loose RAM timings and find the VDRAM you need for the target RAM frequency.
At this point I found I needed 1.85V VDRAM to get my 48GB of RAM past memtest at over DDR3 2000 speed with an uncore clock over 4GHz and 208 BCLK. This is out of spec and the BIOS warns me it could kill my CPU. If you care about your CPU lasting indefinitely you should stick within the official limits which might mean reducing the RAM frequency.
At your target RAM frequency with uncore clock at or above target you can now work to tighten the RAM timings.
Run memtest at least past test 3 for a quick stability test and run as long as you have patience for once you think you have found the stable limit. An overnight run would give you good confidence that your RAM is stable before you proceed to the core.
Once you have done the above, you can leave VTT, VDRAM and the uncore multi alone while you overclock the core by upping the core multi, adjusting BCLK in the range less than or equal to the BCLK for your stable RAM test and increasing VCORE to get stability.
You'll be thermally limited and from this position you might want to reduce the uncore a couple of multis to get the temps down a bit if necessary to achieve your target core frequency but your BIOS may auto tighten your DRAM channel timings when you change the uncore clock multi which can cause instability so you have to watch out for that and set them back to the stable values manually. If you end up reducing the uncore a lot you may want to go back to the beginning with a lower uncore target and work back to this point with a lower VTT which will also help with core temps. You can't lower VTT here without going back to the beginning of the process though because it will impact RAM stability. Uncore can go as low as 1.5 times DRAM with Xeons.
After getting my 48GB RAM stable at 208 BCLK I ended up with 200 BCLK for my final overclock and I left VTT and VDRAM at the 208 BCLK settings so I know there is some headroom there.
Similarly with the core overclock I found VCORE for 4.8GHz and run that VCORE at 4.6GHz daily so I know there is some headroom there too.
I took so long to write this you are already done. Maybe you can try when your new cooler arrives.