My PC refuses to boot to bios when set for all or 3 CPU cores. I haven't been able to

establish for sure whether it's the CPU that's fried or the Motherboard. Perhaps it's

a voltage feed or capacitor or something that's the problem..

 

Does anyone know of a way to establish which it is when you don't have a swap out

available....?

 

That would be cherry vanilla if it was only the MB... and the love for the CPU would

take on new heights.

 

....also Why 2 cores blown? I only have settings in the bios for - "Use Core 1, 2, 3, ALL,

now if I select 3 cores ... which 3rd core is it trying to use... a bad ONE when possibly

there's another good one that's not getting attempted ? (so perhaps only 1 core is blown)

 

ALSO - When I sat it for 3 or ALL cores it's the 'VGA' red led that stays lit, not

the CPU red led.

 

Perhaps thats a clue that it's the MoBo...

 

Can anyone help ?

 

Thanks

aero

My PC refuses to boot to bios when set for all or 3 CPU cores.

You have to reset the CMOS.  There are various procedures for resetting the VAS depending on the type of MB installed (i.e., ASUS, Gigabyte, etc.). Here's a link on how to do it for some systems: http://pcsupport.about.com/od/fixtheproblem/tp/clearcmos.htm.

 

I have the ASUS MB and I just unplug the system, go to the MB and near the battery there is a CMOS reset button. I hold down on that for a few seconds, plug in the system and restart. It will set your BIOS back to the default.

 

Best regards,

Thanks for posting this link, Jim. It is handy for a whole host system solutions.

Thanks Jim.... wish that was the problem. Ordered second hand board.... coming tomorrow. Fingers crossed

 

aero

It is very difficult to fry your CPU or MB so I'm shocked the CMOS fix did not work. How did you determine it was the MB and not the CPU?

 

Best regards,

well ... I haven't established that... after searching forums etc and asking in here, it seems that there's no feedback on ascertaining this. Therefore I tried to assess all the clues and nuances that I noticed.

 

1 After fault, CPU and board allowed running with 2 cores

guess chances are the CPU would go down completely

2 MB fault indicator LED stopped on 'VGA fault', tested

GPU OK

3 Swopped out RAM all OK

4 With RAM removed Beep Code indicated VGA fault.

5 MB does not have CPU onboard vga circuitry

6 Have had previous similar MB go down with VGA fault with

this same CPU.

7 Was running a clocked GPU card at the time of the faulT

and at the same time running the CPU at 5.226ghz -

loading board components supplying voltage, regulating

etc...

 

.... not at all scientific and really guesswork.... that is why to hedge my bets I found a MB CPU RAM and cooler bundle deal second hand on eBay for same CPU and MB ... will sell on what's not required... should end up not costing a lot for the repair, all going well.

You wouldn't even get any of those readings if the board when down! I have a feeling you did not try to reset the CMOS or you did it incorrectly. Once you get into the BIOS, you reset everything to the default and move on.

 

Best regards,

I have had the board completely out of the PC, with the ram, GPU, cpu and CMOS battery removed to examine the board for physical clues. At various times when trying to get the board to post beep I have switched the reset handbag after disconnecting the power ... ohhhh

 

sorry ... I know now why your confused by my early posts..

 

The latest situation with the system is it won't post, it stops with a 'VGA' fault... this happened when I decided to try and get it running on 4 cores again... I set the bios to run the CPU on 4 cores again just to see if it would work again... but it then refused to post and despite numerous attempts at clearing the CMOS it won"t post.

 

 

So to recap, the board is now not posting and is showing a 'VGA' fault light although the GPU is good..

 

Sorry for any confusion.... been a lot of trying this and trying that over past few days...

 

aero

.

Thanks for the explanation. Now I'm more confused than ever! If you can get into your BIOS, your system posted. It sounds like you have wrong settings in the BIOS and you need to return everything to the default and start over again messing with the cores.

 

I'm going to move this to the Hardware section as that is where the computer experts reside.

 

Best regards,

..just to clarify, Jim... the board is not posting now. That's why I can't get back into the bios....

 

I didn't realise there was a Hardware section... you're right this thread would probably be better addressed there.

 

Thanks

aero

UPDATE-------

Have purchased 2nd hand i7 2600k cpu to replace the blown one... set it up on max settings and did a little test flight.....

https://www.youtube.com/watch?v=1MJ3...ature=youtu.be

aero