Memory trouble with 790FX-GD70

Question

Hi,
Last Saturday, I bought everything located in my signature. There seems to be a problem with the mainboard and the memory, though.
I couldn't install Windows 7, without removing some of the memory, XP went fine.
When running windows, either 7 or XP, with the 8 GB in the pc, it freezes, gives BSOD's, reboots..
I've done a memtest, with all for memory modules, I get errors. If I only have 3 modules in the board, the memtest runs fine. Every memory module in itself works fine. Every slot on the mainboard in itself works fine..
I don't know what might be causing the problem. The mainboard should be able to work with 16GB of memory, why would it fail with 8?

Answer 1

Quote from: Hans on 13-August-09, 01:13:52
When you install 3 dimms, the memory runs in single-channel mode which is less demanding on the memory controller which is inside the CPU.
Installing 4 dimms will make all run in dual channel mode which the memory controller cannot handle with 4 dual sided memory dimms. Four single sided dimms can be done. That's why there are 4 dimm slots. And, on top of that, some people seem lucky and can make it work, but they often need to lower clock speed and loosen timings manually.
Reason for all this: it's simply the limitation of the memory controller in the cpu.
Thanks for the information, you've taught me quite a bit.
Quote from: Stu on 13-August-09, 01:46:10
Both are 32bit? In which case you're wasting your time with 8gb of RAM, as you can only use over 4gb with a 64bit OS and 64bit software. There is no point having more than 4gb if you're only using 32bit OS and software, as the rest is unuseable.
No, Win7 RC is 64bit.