Help with Venice OC

[Penley]

Hey guys, I need some help with my overclock because I've run into some problems. First, my specs are:

[*]AMD64 Venice 3200, LBBLE 0516DPHW
[*]DFI UT NF4 Ultra-D, 4.14-2 BIOS
[*]2x512 OCZ Value VX
[*]PowerColor Radeon X800XL 256MB
[*]OCZ PowerStream 520W
[*]XP-90 + Panaflo 90mm fan

I've been trying the method of testing the maximum of each component (HTT, CPU, Memory) so that I can see how far I can push the CPU and board. So far I've been able to get the following:

HTT Max: 285 with CPU@1.6V, mem 1/2 divider, 7x multiplier, 2.5 HT Multi
CPU Max: 2550MHz with CPU@1.6V, mem 1/2 divider, 10x multiplier, 2.5 HT multi

I'm having trouble with overclocking the CPU. I started out using the 4.14-2 BIOS and I got up to 2700MHz doing 8M Pi calculations and P95 Stable for 5 minutes. So I tried both the 3.10 and 5.10 BIOS but was unable to get above 2500MHz. I then flashed back to the 4.14-2 BIOS but I have been unable to get above 2550MHz without getting a PFN_LIST_CORRUPT or IRQL_IS_LESS_THAN Blue screens of death! What's the deal? Also, I notice a weird problem. I'm using Stress Prime">http://sp2004.fre3.com/</a> to test stability and almost always it crashes when I try to stop the test. Last night I ran it for 10 hours with the CPU at 2650MHz with no errors, but as soon as I tried to stop the test, blue screen of death!



I have not yet started testing max memory so I don't yet know how good the Value VX is. I know that it won't boot to windows when I tried to set it on a 2/3 divider for 250HTT at 2.5-3-3-7-1T-3.0V.

So my questions are:

1) Why would the computer crash only when I stop P95?
2) Is there anything I can try to get a better max CPU and max HTT Speed?
3) Is 1.6V too much for a 24-7, (hopefully) stable system that's going to last at least a year?
4) Still another question is that I set the vcore to what should be 1.62V in the BIOS, but both MBM5 and CPU-Z say it's only 1.58V. Both these programs consistently report voltages that are lower than what the BIOS says. Which one is correct?
5) Is there any other general advice you might have for improving this setup?

Thank you very much for any help or advise you guys might have to offer!

 

[Penley]

bump? Anyone have any advise?

 

[n7]

Loosen RAM timings?

 

[Penley]

Would that make a difference when I have ram set at the biggest divider?

Mainly, though, I'm wondering if anyone knows why Prime95 would be only having problems when I stop tests.

 

[Frown66]

1. Don't know. Maybe RAM related, see my #2 response. BSOD are usually ram related.
2. Loosen your RAM timings. I know the DFI + Venice combo can be really picky with ram running at 1T. It maybe fixed in a new bios somewhere down the road. For now, run the ram at 2T. Use a divider. Try to get RAM out of the equation as a overclocking limiter. Set HT to 3x. I don't think A64's like .5 increments in anything.
3. I don't know about 1.6v on the cpu. I hope its good enough. I'm running at 1.61v with the same HSF combo as yours (xp-90 + panaflo 90mm fan). Temperatures are fine and its been stable for a few weeks.
4. I *think* the motherboard settings are max cpu voltages allowed, so I don't think the cpu is constantly at the max volts. I could be wrong as I'm just guessing here.
5. Not really. Did you use some good thermal paste for the heatsink application? I know that can help cooling the cpu by a few degrees. Every little bit helps!

 

[Concillian]

For what it's worth, I see the same thing.

My conditions:
RAM tested at 1:1 with low multiplier to be stable at ~200 Mhz
CPU tested 24hours stable at xxxx MHz with 1:2 divider
Set CPU and memory so both are slightly below their individual maximums and the BSODs start rolling in.
Independent of using very high HTT and low multiplier or vice versa (8x300 vs 9x267 both give the same result when memory frequency is similar (and below 200 Mhz.)

 

[Penley]

Okay guys, you were definitely right about it being a RAM related problem. Last night I increased the RAM volatage to 3.2V (max w/o using the special 4V jumper) and lowered my timings to 3-3-3-7 2T. I was able to get the RAM up to 240 at 1:1 divider. So I tried 2600MHz with a divider and it had no problems in prime. I left it priming over night at 10x270 with the 4/5 divider (RAM running at 225MHz) and it it had errors after 7 hours, but no BSOD!!! I lowered the divider one more notch before work today so I'll see how it handles when I get home tonight.

I will also try the 5.10-2 and 5.10-3 BIOS to see if that can help my memory performance. Thanks a lot for the help! I will report back when I have more results.

 

[coomar]

The 2T vs 1T comparison gets worse at you loosen the timings, your probably better going around 200 with tighter timings, check your memory latency times