P7P55D EVO - bad DIMM slot on arrival?

gtswanny

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Aug 25, 2010
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18,510
Hello all,

I finally got in all the parts to build up a new system. After reseating the CPU several times, and also the memory I was able to get the mobo to POST. I happen to notice that only 1 of 2 G. Skill DDR3 1600 F3-12800CL9D-4GBRL was being recognized. However, I proceeded to load Win7 Pro x64 without a hitch. That went blazingly fast. I did some quick playing around in the BIOS. Turned on XMP and bumped the CPU. DRAM shown at 1600 (albeit only 2 of 4 GBs), CPU at 3.2Ghz. Booted and ran Windows just fine for a while.

I decided to fiddle with the RAM and see what is going on there. Here is what I found:

1)Both sticks work just fine individually in slot B1.
2)Put sticks in A1 and B1 and system only sees one of them.
3)Try each stick in A1 only and system never sees either one.
4)Put both stick is in B1 and B2 and system sees the full 4GB

Is it really as simple as a bad A1 slot and time for RMA?


Additional Sys Spec:

Antec 900
Corsair 850TX
I5-760 (tested stock and slight OC)
SAMSUNG Spinpoint F3 HD103SJ 1TB 7200 RPM
SAMSUNG 24x DVD Burner - Bulk SATA Model SH-S243N/BEBS LightScribe Support - OEM
ASUS EN8400GS Silent (to be replaced)

Thanks for any suggestions!
 
Solution
It sounds like it. Your troubleshooting identified DIMM A1 as not functioning. You don't have to RMA the board, but if you don't, you won't be able to use that DIMM if another fails or you want to populate all the DIMMs.

gtswanny

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Aug 25, 2010
4
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18,510
If I kept the board and used just B1 and B2 then both sticks would be running on the same channel? Then I would be getting less performance since I'm not actually using two channels? Do I have this right? Thanks!