OK so i just got a new build..

Core 2 Duo E6750

Gigabyte P35-DS4

Geil 2x 2gb kit

Windows xp 32-bit

All working great, then i notice a slow down.....



erm wtf pls help thx

Did you do a fresh install of windows? if you just transplanted the HDD from a single core machine and got it to reinstall the mobo then it probably would not have re-installed the hardware abstraction layer (HAL), which allows it to recognise that it has a dual core process.

There is a mechanism to get it to re-fresh the HAL, but I don't know what it is, it has been mentioned on the forums before, maybe 12months ago was the last time I saw the issue floating around.

heres the thing tho it was detecting the two cores! for about a day and a half!

could it have reverted to the old one?

I did do a transplant yes.

i had a feeling it was one core that had died, is it possible through oveclocking to do this? i had assumed the cpu would just not boot.

thanks for the help

just reinstall Windows.

it should clear up problems.

check the bios settings too to see if you somehow managed to turn off the 2nd core. if you were in there f'in with clock settings, who knows what got effected by an errant keystroke


also, a reload of windows may be all it needs

Check the bios for a disabled core setting.
If you can't find a problem with it (and don't mind losing your settings) flash the cmos.
If that still doesn't solve it, reinstall windows.

This makes NO sense whatsoever, i downloaded an updated bios earlier, and re-downloading it fixed it?!

Somebody want to tell me which BIOS option disables a core lmao?

Ive built and fixed a lot of pc's but that is something i have never seen!

Thanks for all the help!

I've also never seen a 'disable this core' bios setting.

I have heard of core reacting differently to overclocking, with one failing whilst another is good, from what I understood they generally survived when brought back to normal speeds, I presume some kind of soft failure, rather than an overvoltage hard smoking failure.

People might have been assuming that the bios had been corrupted in some way, if it was I would not expect it to work at all.

yeah it was kind of odd, now my x-fi isnt working, reinstalled it and everything. in the audio section in control panel it just says 'no audio device' and the boxes are greyed out! but its there all dandy in the device manager.

also when i get to 'windows is shutting down' screen the computer will hang forever until its manually turned off.

i think they are interlinked, any suggestions please? ive already tried a few obvious and less obvious things.

i have a feeling it would be easier just to format and reinstall, is there anything i can use to keep my password lists in IE and cookies and favourites, maybe even installed files, leaving just the windows install to be nuked?

would be a great time saver! (i kno i can get the favs and cookies manually, just a pain, dont even mention outlook!! )

ty

Hey, you should celebrate a defective, shut down core. Some would consider that an engineering feat!


But seriously, I don't think it's a defective core, just some messed up settings. If you continue to have problems upgrade to the latest (NON BETA) BIOS and do a fresh install of Windows.

My computer has an option to enable/disable multi-core functions. Not sure what the exact wording is and I can't reboot my computer at the moment.

I agree here. If any problems persist do what is said above, but make sure to avoid beta bios'. Atleast...that is what i would do. Also...and I know this may sound odd. My friend (granted his CPU is OC'd) started having sound problems randomly. I checked his OC because I always do this when problems arise. Everything looked fine, but just for grins I decided to up a few voltages on his CPU and northbridge and alas...problem solved. I am not saying this is what you are running into, but I thought I would share a vary odd, but yet similar experience.

Best,

3Ball

I haven't seen anything on my new system to disable a core. However, the older systems with P4 - HT, had the feature of disabling HT. So, if you ever ran a P4 with HT, it tricks the OS to think there's 2 cores. By disabling it, it reverted back to one core.

As the others said, reinstalling the OS will fix allot of the HAL problems your having. Also, make sure the ACPI is enabled. When you go into the device manager, expand computer, you should see, "ACPI Multiprocessor PC" More then likely your may say "ACPI Uniprocessor PC".

You should prolly invest in some kind of backup... external HD/USB, or burn your files to a CD/DVD media. I like using Nortons Ghost which makes a copy of the HD on another external device to keep my backups.

Usually you can switch off cores by lowering the voltage. The system will become quite unstable though. I can disable one of the cores of my Pentium D by lowering the voltage below 1.24v.

Disabling cores seems to be one of the more unique abilities of amds spider platform. I´ve read a few reviews of people using a Phenom and disabling a core in the bios to simulate a tri-core and bench it.

On my Intel mobo there's an option called 'Core Multiplexing Technology'

This BIOS setting is present only when a dual core processor is installed.

Description from manual:
"When disabled, turns off all but one processor core. You may need to disable this for legacy operating systems that do not support multiple cores. The remaining core may have access to more cache. The amount of cache available to the remaining core will depend on the particular processor. The increase in available cache can result in
better performance under certain applications."

Hmm, I've got a Pentium D 920 that runs 1.2v with vdroop and both cores are working fine. Is it via the BIOS setting only? If so, I've got to try that sometime.

This may be really stupid, because you said you build systems. But if you have go step the core shuts down automatically to save power when not being used.. I hope you find your problem!! I saw another reader discussing this and then he read it in his manual

Hey guys, i'm have the same problem but when raising my voltage.

I have a E4300 and runs great at 2.7Ghz 1200mhz fsb(/4). However, having recently acquired great watercooling PC4-1025 setup, i have tried to get it up higher. Alot of people have reached 3.2 and 3.4 on air cooling but when i run it at 3.2, after a few days i boot up and the temperature are soaring in the 50's (usually 38 idle - 48 underload) and i can see one core is disabled in the bios. Having an 680i, i actually have the option to disable a core but this time it is greyed out and locked on "disabled". Lowering overclock andresetting to default or even 2.7ghz resolves the problem.

I was wondering if raising my voltages could have this effect, mine being slightly higher than other's with same overclock.

I have looked in device manager and i have ACPI Multiprocessor displayed and the HD has been formatted with this same processor.

Any tips?