ASROCK 939Dual Unstable with 4x512Mb of OCZ Rev2

[amorak]

My problem is this: I had been running 2x512Mb of OCZ PC3200 DDR rated @ Cas2 3-3-6 for the past while on my ASROCK 939Dual-Sata2, and it ran fine at any speed I threw at it.

My problem began when I aquired another 2x512Mb of the exact same OCZ RAM! My board is completely unstable with the 2Gb of RAM, even with the RAM @ 133MHz (so it runs at ~175MHz). I have to crank down the timings and crippled the RAM down to 160MHz effective to get any semblance of stability!

I have also found that when placed in auto, the mobo defaults the RAM to CAS2.5, when putting in 2x512 it defaults to the proper CAS2.

Any ideas on the problem? I have tried reducing the timings, but that does not seem to help...

Thanks!

 

[designit]

4xdimms must be set to 2T. all amd 939 are 2T w/ 4 double side memory in any mobo.

 

[amorak]

I've always ran at 2T, that wasnt the problem

 

[professor1942]

I know a guy who had the exact same problem with 4 OCZ's in another board... I don't think the board is the problem, as I have no problems whatsoever with 4 cheapos (Kingston + Samsung).

 

[SynthDude2001]

Sorry, I can't help ya either...running fine with 4x512 (two different types of Corsair) at 2.5-3-3-7@216MHz here...

 

[designit]

what voltage are those OCZ? might want to check make sure got enough power to mobo. Meaning, what PSU are using. you might need look into Power supply. mostprobably need about 450w and about 30 amps on the rails. have done any vdimm mod?

 

[amorak]

VDIMM volage isn't the problem because

1) They are stable by themselves in pairs of 2x512

2) My board is putting out 2.75v and they only "need" 2.7v

As for a power supply, I would really be suprised, again, if 2x512MB worked, but an extra 2 sticks caused it to need more power. But regardless of that fact, I have a 485w Enermax PS, so power isn't a problem

I am beginning to think it's the RAM

 

[imported_Imp]

Just wondering, which processor (type and revision) do you have? If I recall correctly, the memory controller is on the CPU for A64s and probably other AMDs. Something about A64s and 4 sticks only stable at 333MHZ(160 for you sounds about right).This is only for pre-Venice (Winchester?).

 

[amorak]

Hey Imp,

I am running an Opteron144 chip, which I was under the impression could handle 4x512 @ 2T?

 

[imported_Imp]

I'm not sure about opterons having this issue, but which revision do you have?

AMD Forums

Check out this thread, something about sub-E4s still having a problem. If your CPU can handle it, and you're using identical Ram, then I am of ideas.

 

[pspada]

Asrock support told me they only support 333 on the board with more than one stick of ram installed. I personally run my 3000+ @ 2.43 just changing bios settings, and running my HyperX 3200 at 333.