Prime95 i7 920 - Worker completeing 1 test while others complete hundreds!

[Kibwah]

Hi guys and gals!

I'm new to the forum, however have been skulking around this forum and various other similar forums while fiddling with my i7 920 DO settings

I have come across a problem I have not encountered before while stress testing with prime95, and I cant find anyone who's already encountered it on these forums that might provide me with a fix. It doesn't matter what test I i do (small ffts or whatever), 1 of the 8 workers will complete 1 TEST ONLY while all other workers complete hundreds. For instance, yesterday I left prime running for 7 hours, 7 out of 8 workers completed 214 tests (around about), worker 6 completed 1 test. No errors are reported AT ALL and I do not freeze of blue screen. I come home, everything still running, stop prime, 1 test completed on core 6.

I have not encountered this problem at all untill about 2 days ago, which is when i upgraded my mobo bios (gigabyte ex58 ud3r 1.6) to a newer beta bios. I have since rolled back to the bios i was using previously and I still encounter the same issue. This happens while cpu is at stock settings as well. Have i damaged by cpu possibly?

To reiterate I do not get any errors while stress testing (no prime errors, freezes or bsod). Hardware is i7 920 DO, ex58 ud3r 1.6, corsair domminator 6gb 1600mhz 8, 8, 8, 24 1.65 (ram at stock). Im using most current version of prime95 26.6.

Current O.C settings

multi - 19
blk - 200 (3.8mhz)
vcore - 1.265
qpi - 1.26
dram - 1.66
ram multi - x8
uncore - x16
pll - 1.88
ioh - 1.2
ich - 1.2
pll - 1.88

Thanks in advance. Would appreciate any info regarding this matter

 

[redduc900]

Irregardless of how many hours 7 of the 8 worker threads complete error free, if only 1 thread errors out then your system is unstable. Boot to a thumb drive w/ the latest version of Memtest86+ installed, and check your RAM for stability before going any further. This at the default clock w/ the DRAM frequency set to DDR3-1600 (System Memory Multiplier set to x12 at the default 133 BCLK), and timings manually adjusted to 8-8-8-24 and 1.65V. Make sure all voltage settings are reverted to Auto, except Vcore which should be manually adjusted to 1.12 - 1.15V, and QPI/VTT voltage set to 1.15V.

 

[Kibwah]

Thanks for the reply, I am testing this now

Just to confirm though I never actually received any errors while priming. 0 warnings and 0 errors on all workers.

 

[bennoculus]

If you got no errors on any of the cores, you should be stable. I have heard of a problem before very similar but never figured out what caused it. The guy was having an issue where a worker on a core/thread completed considerably less amounts of tests than the other cores/threads.

Were you using the computer while you were stress testing (as in browsing the web/any other basic task)?

 

[Kibwah]

In the particular instance mentioned in my o.p I was not using the system. It doesn't seem to make a noticeable difference if I am using it or not however.

 

[Kibwah]

I also saw SIMILAR threads none of them seemed as extreme as mine which is why I thought something may be wrong. Other than the prime issue I have no dramas at all, the system appears to be completely stable.

 

[Kibwah]

Ran memtest overnight twice. Once at settings recommended above and another time at my overclock settings mentioned in my first post. No errros. Ran prime95 overnight again also and again no errors. 280ish tests on all workers except worker six which completed 31!

 

[Kibwah]

Bump

Does no one have any insight as to what may be causing this? Or do I have nothing to worry about?

 

[killerkid]

Try and download intel burn test or linx or occt and run those. See what kind of gflops you are getting compared to others. Also check to make sure all cores are at 100% while running them. It might seem basic but who knows maybe that 1 core is only running at 30% for some reason.

 

[Kibwah]

I get 42gigaflops on a single test. I only ran it once I figured an average amount would be a bit less than that. According to this list http://www.techpowerup.com/forums/showthread.php?t=94721 I should be getting over 50. I have a vague memory of getting around 52 when I had done this test in the past, and that would have been at a lower clock speed. I could be mistaken though...

Task manager shows all 8 threads running at 100% while stress testing.

 

[Kibwah]

OK so i think something is definitely wrong here. I've just discovered that when im running optimized defaults i get Unable to detect some of the hyperthreaded cores error msg in prime. I've never had this error before, let alone at optimized defaults

I do not get this error when I am overclocked.