X58-UD7 Memory Issue

[Sparky8971]

I finished my build and now having a memory issue. Everything is stock, no overclocking. I have 12GB of Corsair memory. During post, sometimes BIOS reports 10GB instead of 12gb. When I power off and power back on, it will then see 12GB. Once the system is up everything works great. I tried reseating the memory that didn't help. By the way, this only happens maybe 1 out of 5 times when I power up, so I suspect something fishy with the BIOS. I've run memtest86 and it doesn't see any errors. Also flashed the lated F5 BIOS. Seems many other people have experienced memory issues with this board. Anybody have any ideas how to fix? 

[metal_god69]

have you tried running 6gb instead of 12? 

[rabeel]

I have the same problem on my x58aud3r board.

[Sparky8971]

No, i haven't tried 6gb.. it's such an intermittant problem and for the most part it usually boots all 12gb. The system is extremely stable, no BSOD's, Memtest86 stable, Prime95 stable. I may end up just living with it.
I have a 4gb set of DDR2 memory. I might throw it in just to see if I have any issues. If I do, then I would be inclined to believe it's BIOS related. Sure would be nice to know one way or the other. 

[metal_god69]

Have you tried updating to the latest F6 bios?  I just noticed it now on the Gigabyte page.  It says Enhanced memory compatibility so I think you may want to consider it if you are still having the memory problems...

Cheers

[Sparky8971]

Yes, tried F6, still having problems.
Here is what I'm seeing now. Took out 2 DIMMs and now it boots with 6GB and 2GB hardware reserve. If I power off and power on it comes up normal with all 8GB. But I've noticed if I leave the system off for about an hour and power it up, it will revert to the 6GB/ 2GB hardware reserve. If I want it normal i just power off and on and all 8GB is seen. The same thing is happening with 12GB installed, 2GB is being hardware reserved (intermittantly). I don't think it's a memory problem, cause i power off and on, and no more hardware reserve.
I read a post that suggest the problem is BIOS related not reading the memory SPD correctly at boot.
Could this be the problem?
 

[Sparky8971]

Wow, found this article with other people having exact same problems, but with Asus MB. Folks have resolved by replacing memory even though the memory passes memtest86. Very interesting

http://www.tomshardware.com/forum/266829-30-corsair-reverts

[Sparky8971]

Well, took a chance went out and spent $300 on a new set of memory. Problem solved. Looks like memory can cause these problems even though it passes memtest86, and sometimes boots normally with all installed memory. No more reduced memory during cold boot, no more hardware reserve problems.  Before taking drastic measures like tearing out your MB reseating your CPU, CPU cooler, etc. Try a different set of memory.
Anyway, thought I'd pass this along for anyone else having similar problems.