Stability problems in overclocking

[aznxk3vi17]

So I just got my new box.

Pentium E6600
eVGA 680i SLI A1
OCZ-8500 Reaper 2x1g
eVGA 8800GTX
OCZ GameXStream 700W
CM Stacker

I wanted the best. I got it, but it doesn't seem to combine very well. I got my E6600 to 3.6GHz, and my RAM to 1164MHz. Using Prime95, I tested the processor and memory separately. Actually, I tested the CPU overclock with Orthos, then tested the memory with Prime95. Each by themselves were overnight stable.

Then, when combining it, I ran Orthos on Blend. After about 40 minutes (and sometimes even less), it would give a rounding error.

What do I do? Is there something else I'm missing here when I combine the overclocks?

 

[igloo15]

Hmm the same thing happens to me I am not sure the what the problem is?
I have same rig too except motherboard

 

[aznxk3vi17]

Interesting... I might add that I am running Unlinked (if that wasn't obvious already), so that should eliminate any possible problems with the memory and cpu speeds being a problem for each other...

 

[The-Noid]

NB is getting hot running blend. Cool it better.

 

[aznxk3vi17]

It's already got the heatsink + fan... I don't know what else I can do for it.

 

[igloo15]

The other thing I notice is that in orthos it says I have a 3.6ghz oc when I am only doing a 3.2ghz oc speedfan says I have 3.6ghz oc too but cpu-z and intel tat say 3.2ghz.
I will have to check NB temp when I get home hadn't though about that.

 

[MarcVenice]

Funny thing is that I've read oc-ers say that orthos blend isn't holy. They basicaly said that if it would fail on orthos blend, it wouldn't mean that your rig wouldn't be stable running games or encoding/decoding. I do think it means your pushing it, and might want to back of a little for safety.

Also, can you give your ram a little more voltage ? 40 minutes is quite some time though, so could mean something is running hot as well. Whats your load temps at by the way ?

 

[aznxk3vi17]

I don't know how to check the temperature on the NB specifically, but my case temps hardly ever break 40C. With the heatsink and fan on the NB, I don't know if I can say it'd be overheating. Perhaps I should up the voltages going to the SPP?

 

[aznxk3vi17]

Originally posted by: MarcVenice
Funny thing is that I've read oc-ers say that orthos blend isn't holy. They basicaly said that if it would fail on orthos blend, it wouldn't mean that your rig wouldn't be stable running games or encoding/decoding. I do think it means your pushing it, and might want to back of a little for safety.

Also, can you give your ram a little more voltage ? 40 minutes is quite some time though, so could mean something is running hot as well. Whats your load temps at by the way ?

The CPU peaks at around 65C. I ran the CPU by itself at these temps and they were stable. Funny thing is, I have a Thermalright Ultra 120 extreme. You'd think I'd have slightly better temperatures than this. I even reseated it after seeing those temps, but I only got slightly better temps than before. Still, it idles at around 37C @ 3.6GHz. I don't think the CPU is getting too hot.

The OCZ -8500 Reaper has heatsinks + heatpipes, so I doubt they're overheating. Again, it could be that I need to feed more voltages into the SPP. It's at I believe 1.4V right now.

 

[mgutz]

If it's failing on Orthos blend it can be either memory or CPU.

Test the memory with memtest in DOS, specifically test #5 for several passes for a quick stability test. For a thorough memory test run all the tests for 24 hours. I've seen tests fail in the 13th hour (this was in the middle of day when the ambient temperature was at its peak) so 24 hours might not be necessary if you run the tests when the room area is at its hottest. Then you can rule out it's not your memory. To stress the CPU, try Small FFT orthos for a quick check. Then, for complete stability run blend for 24 hours.

 

[aznxk3vi17]

I also had another question regarding overclocking, specifically towards my RAM.

Consistently on sites I see RAM getting near 6k scores in memory bandwidth in SiSoft. http://www.overclock3d.net/reviews.php?.../ocz_reaper_hpc_pc28500_2gb_ddr2_kit/4 for example. Even with my supposedly unstable overclocks, my RAM never breaks 5500 in the Memory Bandwidth test. It's clocked about the same, has the same timings, hell, even my RAM is the exact same. Before you say it's the chipset, Anandtech's own 680i testing showed similar results. Did I get bad RAM? Am I doing something wrong somewhere?

Also, answers to my stability question would be much appreciated

 

[aznxk3vi17]

Originally posted by: mgutz
If it's failing on Orthos blend it can be either memory or CPU.

Test the memory with memtest in DOS, specifically test #5 for several passes for a quick stability test. For a thorough memory test run all the tests for 24 hours. I've seen tests fail in the 13th hour (this was in the middle of day when the ambient temperature was at its peak) so 24 hours might not be necessary if you run the tests when the room area is at its hottest. Then you can rule out it's not your memory. To stress the CPU, try Small FFT orthos for a quick check. Then, for complete stability run blend for 24 hours.

Yeah, I was going to run Memtest86, when I realized that I lost my original disc, and I had no more blank CDs to burn it! I hadn't had time to run out and buy more, but it's on my to-do list. I also ran Small FFT Orthos overnight for the CPU... it ran fine.

My suspicions point to my RAM, but I can't know for sure... yet.