Prime95 Error - Please Help...

RoEy

RoEy

RoEy

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Hi all,

Ran into a problem. I decided to try and get 4ghz 20x200 stable.

Core i7 920 D0

Vcore - 1.30635
VTT - 1.3065
CPU PLL - 1.812
VDIMM - 1.65
IOH / ICH - all auto
CPU Spread Spectrum - disabled

Ram at 1600 8-8-8-24-1T

Passed 30 Max Runs on IBT

Started to run Prime95 and I get an error after 40 mins:

FATAL ERROR: Rounding was 0.5, expected less than 0.4
Hardware failure detected, consult stress.txt file.

Prime was still running but it was running at a load of 87%. I had the perfomance manager open and saw all 8 cores but the 3rd one was hardly running, hence the 87% load.

My CPU hasn't died has it? I'm guessing I need just a small bump in either VCORE or VTT or even both?

Temps were fine - 68 65 67 64

Hope someone can help.

Thanks,

RoEy
 
Last edited:
No your CPU hasn't died, if prime just has an error rather than managing to crash your computer on a slightly unstable overclock it'll just stop running on that core. Give it a little more Vcore, not sure if it'll need more VTT too but you might.
 
Cheers mate. I think I'll give it a nudge on both vcore and vtt.

Thanks again,

RoEy
 
Another error!

I upped vcore and vtt one nudge and started prime again.

Got this error on the 1st core after 14 minutes:

FATAL ERROR: Resulting sum was 2.099013477481677e+016, expected: 2.127392654314129e+016
Hardware failure detected, consult stress.txt file.

I'm starting to think it's not vcore or vtt I need to up as before it was fine running IBT 30 Max mem runs.

IOH voltage maybe?

Running BLEND by the way.

Need help :(

Thanks,

RoEy
 
Last edited:
Try running small FTT if that runs error free then it suggests that the memory controller or ram needs more volts. oww and drop the RAM Back so it's running under spec so it's not a factor in the failing overclock.
 
Last edited:
Yeah, Prime blend errors are normally CPU voltage or RAM voltage. Either that or 1 or both are at or close to their limits.

I would just bump the vcore a touch and maybe the RAM voltage too and see how it goes. The only other thing that might need a very slight boost would be the MCH/Northbridge.
 
Diggsy said:
Yeah, Prime blend errors are normally CPU voltage or RAM voltage. Either that or 1 or both are at or close to their limits.

I would just bump the vcore a touch and maybe the RAM voltage too and see how it goes. The only other thing that might need a very slight boost would be the MCH/Northbridge.
Click to expand...

I've left vcore at 1.30625 and I've upped the VTT 1.3250 and so far so good. Been running Prime for over an hour now.

Finger crossed!

Must say the help on here is a lot better than Xtreme Systems. People just tend to get annoyed with you on their if you don't know everything about everything.:(

RoEy
 
Nocky24 said:
Personally i'd go for a 21x or a 19x cpu multi for better stability.
Click to expand...

Surely if it passes 8 hours prime, 20 max mem runs IBT and 10 passes of Memtest it's stable?

I'd like to go 21x200 but I think I need around 1.34 for both vcore and vtt and when it's load it goes above 1.38 on vcore which is too much in my opinion.

RoEy
 
RoEy said:
Surely if it passes 8 hours prime, 20 max mem runs IBT and 10 passes of Memtest it's stable?

I'd like to go 21x200 but I think I need around 1.34 for both vcore and vtt and when it's load it goes above 1.38 on vcore which is too much in my opinion.

RoEy
Click to expand...

Yes of course thats stable. Go with whatever suits you best ;)
 
DOH!

Must have spoken too soon. Got a BSOD, after 2 hours 40 mins.

I give up with the 20 multi.

Blue screen said something about service exception?

got this when I rebooted:

BCCode: 3b
BCP1: 00000000C0000005
BCP2: FFFFF96000298B30
BCP3: FFFFF8800551D740
BCP4: 0000000000000000
OS Version: 6_1_7600
Service Pack: 0_0
Product: 256_1

I really want the ram at 1600 and I want 4ghz but I don't think it's going to happen.

Should I update the BIOS? Running 1504

Help.....Please....


RoEy
 
Hi all,

Ok so I went back to the drawing board and determined what my lowest voltage was in order to boot and stress.

Vcore - 1.21875 - (1.208 in CPU-Z)

VTT - 1.25 - I set this so it wouldnt drop below 1.20 - .5v within ram.

VDIMM - 1.65

I have turned all power saving options off, spread spectrums disabled, LLC enabled, turbo, C-tech and C1E disabled, all other voltages are set to auto, including CPU PLL. Memory timings have been put in - 8-8-8-24-1T.

I then set multi to 21x (sod doing 20 again ), DRAM frequency, UCLK and QPI was set manually and I always kept ram below 1600 depending on BCLK. My aim was to see how far I could push the BCLK at stock voltages, increasing the bclk by 10 after each stress. All testing was done on Prime95 Blend test, 8 threads which I ran for certain periods of time then stopped. Towards the later stages I've used IBT 20 Runs Max Mem too. When I get to 4ghz/4.2 I intend to run Prime for 14-16 hours.

Results so far:

21 x 133 = 2.8Ghz

Prime Stable for 2 hours - Temps - 54 52 53 49


21 x 143 = 3Ghz

Ram = 1433 - 8 8 8 24 - 1T

UCLK = 2866

QPI = 5161

Prime Stable for 1 hour 15 - Temps - 57 53 55 51


21 x 153 = 3.2Ghz

Ram = 1533 - 8 8 8 24 - 1T

UCLK = 3067

QPI = 5242

Prime Stable for 1 hour 15 - Temps - 56 53 55 51


21 x 163 = 3.4Ghz

Ram = 1306 - 8 8 8 24 - 1T

UCLK = 1614

QPI = 5883

Prime Stable for 1 hour 15 - Temps - 58 54 56 52


21 x 173 = 3.6Ghz

Ram = 1387 - 8 8 8 24 - 1T

UCLK = 2775

QPI = 6244

Prime Stable for 2 hours - Temps - 59 56 58 53


21 x 183 = 3.8Ghz

Ram = 1467 - 8 8 8 24 - 1T

UCLK = 2935

QPI = 6605

Prime Stable for 3 hours - Temps - 61 58 60 55

IBT Stable after 20 Max Mem runs 8 thread


Ok, I've noticed that when cpu is 100% load the vcore goes up to 1.25 and the VTT tends to drop to around 1.22-1.24 (Everest and LCD Poster readings).

This is as far as I can push the system at these volts.

I've booted into windows with:

21 x 193, stock voltage but I get a BSOD within a minute of just being on the desktop.


BSOD Error = IRQL_NOT_LESS_OR_EQUAL

Tech info = 0x00000000A (0x0000000000008006, etc.......


Now I'm guessing it's either a bump in vcore or vtt or even both. Do I need to set CPU PLL to 1.812 instead of auto also.

I've put loads of effort into this as you can see and now my wife hates me, but I'm so close to 4ghz / 4.2 that I can't stop now.

I'd love to get 4.2.

Hope anyone can help as I've listened to you guys about starting from the bottom and working my way up! lol

Thanks,

RoEy
 
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