Wierd behaviour of Pentium D
 

I am having trouble running the Torture Test on a Pentium D 3.2G, I get the following error:

FATAL ERROR: Rounding was 0.5, expected less than 0.4

However, this error is only occuring when I "Let program run on any CPU". If I specify it runs on a specific core (either), there are no errors. If I run two instances of Prime95, one on each core, there are no errors.

I have tried reducing the memory speed, and also Memtest returns no errors. Temperatures appear okay.

Any suggestions will be much appreciated!

What are the CPU and mainboard temperature readings in BIOS?

Also, what voltage readings do you see? i.e. CPU, memory, 3.3v, 5v and 12v

What are the mainboard's manufacturer and model?

Don't you mean weird?

[quote=paulunderwood;120088]What are the CPU and mainboard temperature readings in BIOS?

Also, what voltage readings do you see? i.e. CPU, memory, 3.3v, 5v and 12v

What are the mainboard's manufacturer and model?[/quote]

Thanks for your reply Paul, here is the info':

Temp at idle = 40C
Temp at full load = 60C

CPU voltage (from BIOS) = 1.3V
Memory voltage and others = no entry in BIOS
(Should I be using a software tool for this? SiSoft SANDRA?)

Motherboard manu' = Gigabyte
Motherboard model = GA-8I865G775-G-RH

Since my previous post, I have replaced the RAM with DIMMs from another PC, but this made no difference. I have also replaced the PSU with another unit, and this made no difference either.

I suggest that from BIOS you set the "Load Fail-Safe Defaults" option and then retest with Prime95/mprime. If this fails again, under "MB Intelligent Tweaker(M.I.T.)", up the "DIMM OverVoltage Control" by "+0.1v" and retest with mprime/Prime95 and let us know whether you system is more stable...

[quote=paulunderwood;120131]I suggest that from BIOS you set the "Load Fail-Safe Defaults" option and then retest with Prime95/mprime. If this fails again, under "MB Intelligent Tweaker(M.I.T.)", up the "DIMM OverVoltage Control" by "+0.1v" and retest with mprime/Prime95 and let us know whether you system is more stable...[/quote]

Thanks for your time with this Paul!

Okay, I went with "Load Fail-Safe Defaults" and errors are still occuring. I increased the DIMM voltage by 0.1, and this didn't help either.

Btw, I also have the latest BIOS revision (F3).

Ok, thanks.

Can you identify your processor? This [URL="http://processorfinder.intel.com/List.aspx?ProcFam=2112&sSpec=&OrdCode="]list[/URL] might help.

What are your memory modules? Manufacturer(s), model(s), frequency?

[quote=paulunderwood;120138]Ok, thanks.

Can you identify your processor? This [URL="http://processorfinder.intel.com/List.aspx?ProcFam=2112&sSpec=&OrdCode="]list[/URL] might help.

What are your memory modules? Manufacturer(s), model(s), frequency?[/quote]

This is the processor (it is a 3.4, not a 3.2 as I wrote earlier):
[URL]http://processorfinder.intel.com/details.aspx?sSpec=SL9QQ[/URL]

I have a single DIMM fitted:

Manu': TwinMOS
Model: M2G9J16A-TT (512MB)
Freq': PC3200
CAS: 2.5

Okay, I am running out of ideas. My final guess is: at a temperature of 60C the chip is close to its maximum. Do you have adequate case cooling? If you can, try cooling the chip more, possible by running with case side removed and, further, with a fan blowing on the CPU area somehow. Are you using a standard Intel CPU heatsink and fan? You just might need a better heatsink and fan.

Ps. try [I]underclocking[/I] the CPU, say 3.0GHz i.e. "CPU Host Frequency" at 171MHz

[quote=paulunderwood;120141]Okay, I am running out of ideas. My final guess is at a temperature of 60C the chip is close to its maximum. Do you have adequate case cooling? If you can, try cooling the chip more, possible by running with case side removed and, further, with a fan blowing on the CPU area somehow. Are you using a standard Intel CPU heatsink and fan? You just might need a better heatsink and fan.[/quote]

I am using a Zalman CNPS-7000B cooler, which is usually a very effective cooler. I have been running it with the side removed and in a cool room.

I will try reseating the cooler with some fresh paste.

The error is occuring almost immediately after starting the Torture Test, and only when I set Affinity to "Let program run on any CPU". It works, if I assign Prime95 to a specific core. It's all very odd!

I'm starting to wonder whether I have a motherboard problem.

Many thanks for your assistance!

[quote=paulunderwood;120141]Ps. try [I]underclocking[/I] the CPU, say 3.0GHz i.e. fsb at 171MHz[/quote]

Sure, I will try this now.

[quote=paulunderwood;120141]Ps. try [I]underclocking[/I] the CPU, say 3.0GHz i.e. "CPU Host Frequency" at 171MHz[/quote]

I have set it running at 171MHz and 150MHz, and the errors are still generated - but, they take several minutes to occur.