You probably are having these problems cause you have loaded your memory controller to the MAX. However, the X-58 board you have is a stable board once you have it configured properly.
We need to take things from the start:
First I need you to run it using 3 DIMMS "tripple channel" using the XMP at 1.65v
Since this is supported by your board & your rams
If it works then load the default setup BIOS & add one DIMM at a time
Your board supports the i7 990 & it should run like a champ
start with this & keep us updated
To answer your question about the different frequencies.
Your memory controller reads the RAM speeds at 1066 but, it will also read them at 1600 through the XMP since you are not OCing your CPU. However, since you are using the highest RAMS supported by your board the controller is somehow being stressed.
To make a long story short start with what I suggested & we'll take it one step at a time
Thank you for answering, Ziad.
Yes, it is what I'm doing right now, running 3 DIMMs Triple Channel XMP-1600 @ 1.65v. And yes these are the best settings at the moment as I figured out, but it still fails memory test by freezing. By best I mean it does work longer with high-load apps, but eventually it freezes anyway.
Yes, I also tried loading BIOS defaults and running sticks one-by-one (also testing slots in a same fashion). So all 6 sticks I got failed it, the only difference was the time they took it to fail.
Thanks again for your help. Take care.
Then you might have to consider testing different RAMS
Also take into consideration:
Is your PSU a stable single rail PSU? The X-58 chipset works best on a good single rail PSU with at least 600W cause you have a six core CPU
So, is you rig well powered?? & is your CPU well cooled?
The X-58 is somehow an old system. So how long have you been having this issue??