E6600 only one core working What might have happened?

Hi Everyone. Happy New Year

I did do a search but couldn't find anything like this error on the forum.

I have a Conroe E6600 on a gigabyte 965-DS4 Ver1 mobo with a stock Intel fan and 2x OCZ 1GB memory.(with Heat sinks as standard.)

The other day I noticed that my computer was working much slower than in the past so much so that I thought I would have a look at what processes might be dragging performance down.

To my horror I discovered that I only had one core showing in Task Manager. Note trusting MS apps I decided to run other apps including TAT and CPU-Z and Core Temp and they all reported the same thing - I only have one core active, the other just seems to have vanished (or more specific Died.)

When I first purchased the CPU I kept getting fan failure notices from the Mobo and on checking found that the Fan would not start spinning when the computer was started but would start say 15sec later just long enough to get the annoying Fan error tone.

I took the CPU back (they won't just take the Fan back) and waited about a month before I was given back my CPU with what looked like a slightly later model fan. Same thing happened with this unit also.
I changed the settings on the mobo to prevent it from Auto speed to fixed speed. This stopped the Fan errors.

So I have been using the computer for about 14mths (have to find receipt!!) and only noticed this in the last couple of days.

Has anyone seen this type of problem before?
Is it a mobo or CPU problem? (i.e. Mobo disguise cpu info.)
Does anyone know if Intel will cover a fault like this under their warranty policy?

11 answers Last reply
More about e6600 core working happened
  1. What is your BIOS reporting?

    If your BIOS sees it but not Windows, you likely have a Windows Issue.
    If yoiur BIOS does not see it, you are in trouble.
  2. Thanks for the reply zenmaster

    The bios does see the cpu correctly.
    I have added a screen shot of the application's I used to identify what it is reporting. This might make it a bit clearer.

  3. Check your BIOS for an option called "Core Multiplexing Technology" and make sure this is 'enabled'.

    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.
  4. I've had another look at the BIOS but I don't have that option.

    Interesting concept Core Multiplexing, I couldn't find any hard evidence that actually used on current systems.

    thx for reply.
    I'm starting to think no one has seen this problem before.
  5. For the fan, it's normal with this board that the fan won't spin directly after the cold-start. After certain CPU temp, then the fan will start spinning (set on auto). You just need to disable the fan notification in BIOS for the annoying sound.

    After 14 months...mmm...kind of strange. Were there any power outage before this happened ? Does your PSU's voltages are in normal value ? Have you try to reset the BIOS ? Maybe try to installing your CPU to another mainboard (friends mainboard which support your CPU) to see between CPU failures or mainboard failures.

    If it's a CPU failure, i think Intel cover it, you got 3 years warranty from Intel.
  6. Do a quick check in your Device Manager, and open the tree for computer.

    It should say, ACPI Multiprocessor PC. If it says Uni-processor PC then something got switch on the HAL or ACPI settings. :oops:. o O (I think)
  7. If you go inoto "Device Manager" and select "Computer".

    What Driver do you have?
    Is it "ACPI MultiProcessor"?

    If its not, that is why Windows is not using both cores.
    You can try changing that here, but sometimes changing that driver requires a Windows Reinstall.

    Not sure who that could have gotten changed.
  8. In Device Manager under Processors, if you have two, then see if they're both enabled. If only one, then maybe you should try reinstalling Windows. However, when I installed my friend's dual-core from a single-core without reinstalling Windows, it automatically installed the other processor and became a multi-processor OS after a reboot. If you still have issues, I would look in to a possible motherboard problem.
  9. YOU have a lazy core - put a patch over the good core so it can not see and the lazy core will get better
  10. Thank you for all of your input.

    It seems that while I was playing with the switches in my boot.ini one night late, I inadvertently placed a line in there which effectively tells the OS only to see on CPU core.

    Please close this thread. And thanks again.
Ask a new question

Read More

CPUs Fan