XFX MB-750I + q9550 Quad Core = absolute instability ,Lockups. HELP!

Considering you can't POST with the 2nd RAM module in the 2nd or 3rd MOBO slot, it is one of the two things, the Memory or that MOBO. But considering the 1st stick can POST is all slots and the 2nd stick only is 2 of 4, I'm thinking there is something weird with that RAM module. If you bought good memory, it probably has a lifetime warranty. Exchange that one stick, it should be relatively easy, but first do one more test. Use the 1st RAM stick, unplug ALL peripherals you can; i.e. only run MOBO, CPU, RAM, and a small GPU since yours doesn't have onboard video, and test all slots with Memtest86+ booted off a CD/USB (run for a few passes each slot). Then, if those all pass, do the same with 2nd module. If you have problems again with 2nd and 3rd MOBO slot only with that module, then it probably is that module and explains freezes. Like I said earlier, get it replaced as it should be under warranty. If not under warranty or you don't want to wait, does a friend have a similar spec RAM stick you can use for testing? Once the new RAM module comes in, test it, if it has problems with the 2nd and 3rd slot, it's the MOBO.

I would do this testing first as you could be buying a new MOBO but still have the same problem if it's the RAM.

I have tested 2nd, and 3rd MOBO slots simultaneously! 4 gb!NO Errors! All slots work fine. It did POST!
Watch the screenshot. So it is not a problem than, I did test all slots so far in different configurations and possibilities watch previous posts. What might be the reason for Lock ups and Freezes?

From your post #9 you wrote this:

When I put 2nd RAM in the second MOBO slot (1st RAM stick is taken out) I hear
clipping beep (like broken wiring or something) which turns into 3 long beeps and no
POSTing, try 3rd slot - no POSTing, and I try the fourth slot it does POST and gives
Warning screen ,as before , in red about default settings, I reset and Memtest
starts testing my 2nd RAM stick in fourth MOBO slot. 8 passes - NO ERRORS!

This to me points to a bad RAM stick. However, if you tested all RAM slots and everything tests fine (each stick by itself in every slot), then we are onto something new. It can be power - voltage levels dropping can wreak havoc on a system. Do you have "brownouts" in your area? Is it on a UPS? If it is on UPS, is the power supply bad? Heat can be an issue too. Have you ever removed the CPU fan, cleaned the contact points, put some new thermal compound on and reseated it?

My problem ended up being a timing problem with Windows 8 and a power problem when I was running Windows 7. I live in Africa and we have brownouts, which would cause my computer to lock up. A UPS fixed the problem, now I haven't had a lock up in many months.

The thread is closed! I Moved to another MOBO! People beware of XFX 750i mobo, you will suffer dealing with it.