32GB Samsung Ram (8x4GB Sticks) can't get passed 1600Mhz on Rampage IV extreme

I recently purchased 8 lovely sticks of

Samsung Electronics Extreme Low Voltage 30nm UDIMM 4 Dual Channel Kit DDR3 1600 (PC3 12800) 240-Pin DDR3 SDRAM MV-3V2G3D/US

Previously I only had 16GB (4x4GB) but going to 32GB (8x4GB) in my rampage iv extreme has killed my RAM OC of 2133@ 11-12-12-30 1T @ 1.5v

My VTT CPU and VCCSA are at 1.15v. My Processor OC is 4.5Ghz 3930k

As soon as I went from 16GB to 32GB the system (MasterControl see sig) became unstable. I have had to take the RAM down to 1600 Mhz to stablize it. I read else where that over 8 sticks of RAM in a Rampage IV extreme can make it less stable.

As any one got 8 sticks of this stuff running any faster? If so would you be able to share your settings? It appears to me this RAM OC's well with 2 or 4 sticks but 8 sticks is pushing your luck...

I've tried upping the VTT CPU and VCCSA to 1.2v and the vDIMM to 1.6v to achieve an OC of 1866mhz at 11-12-12-30 1T without joy.

A dude in this thread states that :

'Are you aware that X79 with 3930k, with 8 sticks or RAM, drops to 1333 speed? Won't officially support 1600 or above with all 8 slots full....' Is this true?

Hmmm it seems some have got it while other haven't

Some guys in the Official thread for this RAM are able to OC 8 sticks:

http://www.overclock.net/t/1210482/samsung-2x4gb-low-voltage-ddr3-1600-kit-ocing-to-2400-discussion/890#post_17425847

http://www.overclock.net/t/1210482/samsung-2x4gb-low-voltage-ddr3-1600-kit-ocing-to-2400-discussion/890#post_17433367

http://www.overclock.net/t/1210482/samsung-2x4gb-low-voltage-ddr3-1600-kit-ocing-to-2400-discussion/890#post_17433597

Yeah, sounded like dog s**t to me to!

Do you know what your VTT CPU and VCCSA are set to?

Hmmm, really interesting like I said previously my VTT CPU and VCCSA where both manaully set to 1.15v. I set them to auto like you and at 1600 Mhz ASUS AI Suite II reports them VTT CPU 1.26v and CPU VCCSA @ 1.23. Going to keep these on AUTO now, asus MB engineers probably know alittle more than me here.

When I OC the Ram to 1866Mhz the VTT CPU goes to 1.359v and CPU VCCSA @ 1.237. So my guess is there is some intelligent dynamic ramping of these voltages probably based on how many DIMM's, Speed and maybe timing. Unfortunalty setting these back to auto didn't help me get a overclock of 1866mhz

Bingo, changes the command rate to 2T did the trick, also I was able to keep stock timing of 11-11-11-28. It maybe only a modest RAM oc to 1866mhz, but I'll take it! Tried pushing my luck to 2133Mhz but no dice on the stability front.

Thanks for sharing your experience good to know that it ain't easy getting a good OC with at sticks on the X79 platform

Here's some mem-scores, looking alright!



Compared to stock (with only 16GB here though)



Many thanks for your input on this guys

Cheers dude! I'm liking the additional head room. I got the additional 16GB to play around with RamDISK and RAMCache. Also I plan to use virtual machines for some development work going to give those babies lots of RAM to play with

I downloaded SuperSpeed's SuperCache 30 day trial of RAMCache, it's boosting my benching, not sure I'll notice the real world speed boost, but gives me a warm fuzzy feeling to know it's there.

Used IMDisk yesterday and loaded Crysis 2 on to it, pretty sweet game loads super fast.

Here's my Crystal Mark of a 10 GB RamDisk with IMDisk with my newly OC'ed Ram. One day people will think these speed are slow! Got to love tech man



Wow 24 GB ram disk! May I ask what you use that for?