F3-12800CL-2GBRL with MSI P55M-GD45

[ahjohng]

I have an MSI P55M-GD40 motherboard with 8GB RAM (4 sticks of 2GB G.Skill Ripjaws DDR3/1600 1.5V F3-12800CL-2GBRL). The BIOS sees only 4GB of memory (half), but Windows 7 x64 and CPUZ both report all 8GB. However, only 4GB are usable. If I install only 2 such sticks, again only half of the installed memory (2GB) are seen by the BIOS. I have the latest BIOS, version 1.40 for this board, with XMP enabled.

Interestingly, occasionally the BIOS would be able to see all the RAMs installed, but upon the exit of the BIOS setup, it went back to report only half of the installed RAM. So, this led me to believe there is a timing issue. I contacted MSI and was told that G. Skill RAMs are not in the recommended vendor list.

Other than this problem, my system of i7-860 runs very well. I am very happy with the overclocking features that all components are able to perform together. Notice this issue still exists without overclocking. So, is there anything in the BIOS I should tweak to resolve this issue?

[Tradesman]

Do you have the latest BIOS? 1.4, can be found here:

http://www.msi.com/index.php?func=do...1&prod_no=1894

Also, load base timings, Command rate/timing, DRAM voltage manually, don't use AUTO settings

[ahjohng]

Yes, I do have the latest BIOS, version 1.40.

After doing a more extensive research, I read that my issue is related to the CPU not seated properly. So, I removed the Corsair H50 heat pump and the CPU and studied the mechanism that holds the CPU down more carefully. Sure enough, I did not seat the CPU properly. It is amazing that despite my petty mistake the system can still possibly function so well. So, after I have reseated the CPU, the BIOS now sees all 8MB of RAM. Thanks for your help.

For the 1156 socket, you need to pull the level all the up and then clamp it down. Of course, the problem of my new system is not fully resolved. One of my RAID disk arrays is reported failed which is not related to RAM issues.