32MB issue

[joseph]

Hello, need some advice on best option to address 32MB issues with P9X79 deluxe (BIOS 0802) using 2 sets of F3-17000CL9Q-16GBZH. These are on the P9X79_DELUXE_DRAM-QVL.pdf and show as supported in an 8 DIMM configuration.

First off, Win7 x64 pro would not install with 32MB installed, needed to drop down to 16MB. Install would run from CD but after copying files, upon rebooted would get stop 0xC0000221 for hal.dll or ntoskrnl.exe. After installing windows with only 16MB could later install full 32MB (cleared CMOS) and windows would boot fine. Since then the systems has exhibited some strange behavior but I have not yet narrowed it down to memory vs. another component.

Currently memory running at XMP#2 (2133MHz, 9-11-10-28-2, 1.65v). I am running several tests to find a hard fault, but all tests (memtest, ASUS PC-Diags memory test, prime95) have run fine so far. I?m looking for a stable system to run several VM's for software development & testing. So what would be the recommended option below:

1) return current memory for F3-17000CL9Q2-32GBZH 4Gx8 (although not currently on ASUS DRAM QVL).

2) return current memory for F3-17000CL11Q-32GBZLD 8Gx4 (although not available anywhere in the US, so maybe not really an option for me).

3) keep 2 x F3-17000CL9Q-16GBZH configuration and hope for more stable BIOS in the future, maybe running with only 16MB for now if system is not stable.

4) return 1 F3-17000CL9Q-16GBZH set and give up on 32MB not running as many VM's at the same time.

5) any other options?

Thanks in advance for your help!

[Tradesman]

With two sets, XMP won't work, so disable XMP, manually set timings to 9-11-10-28 2T 1.7 and raise the VCCSA about + .05

[GSKILL TECH]

It'll probably need more than that for VCCSA, 1.25V or more for 32GB DDR3-2133

Thank you
GSKILL TECH

[joseph]

OK, I'll give that a try and re-run the memory tests.

Can you explain why XMP won't work for a setup with 2 kits?

Read on the net afterward that there could be issues with using 2 kits even of the same part#. So no need to get a "32GB" kit, just tune what I have. Awesome, returns are a pain.
Thanks!

[Tradesman]

When you but a set of DRAM, whether it's 2 sticks, 3, 4, 6, 8, etc XMP will set up for that set, the basic timings, voltages, etc, but when you add another set, while the base timings don't change, the advanced timings normally do, so if you have a set of 2 and the tRFC requires say 60, that's what it sets to, however, those sticks might require a higher tRFC to run with 4 sticks more like 88 instead of 60, which will throw things off.