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chrisirwin

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PC not booting after overclocked FSB, no display

I wanted to increase speed of my PC, so I carefully increased the FSB from 133MHz to 146MHz which worked okay. Then increased it to 150Mhz and the PC wouldn't boot at all. Fans came on and HD seemed to make usual noise, but no picture - monitor completely blank. Help - PC now completely dead. I tried removing the CMOS battery for 20 secs and also moved CMOS jumper to clear position - switched on PC for 20+ sec and then moved it back to normal position.  None of this helped. How could I have "killed" my motherboard completely like this? Have removed graphics card and tried using on-borad VGA - still no picture.
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scampgb
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Hi chrisirwin,

Overclocking is not recommended by the manufacturer...

One bit of information that would be helpful - do you get any startup beep codes when you power on the machine?  This can indicate where the problem lies.

Can you also please tell us what motherboard and processor you have?

Thanks
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You can sometimes knock out a component while overclocking, or forget to restore all connections.  If everything is connected properly, things to check are:

- motherboard shorting on case
- CMOS jumper set to CLEAR, instead of NORMAL position
- faulty or inadequate power supply
- bad RAM
- faulty video card
- bad cpu
- bad motherboard

To troubleshoot this, I recommend stripping down the pc to the bare essentials: one stick of RAM, the cpu, and the video card, and reset the BIOS.  Do not include hard disks, other PCI cards, or other peripherals.
Avatar of chrisirwin
chrisirwin

ASKER

Actually its my son's PC and I tried to tell him not to overclock, but you know how it is.....

The motherboard is a Winfast K7NCR18G Pro with Socket A Athlon processor. There are no beeps when one swithces on. The LEDs on the CDROM and DVD drives do light up, as does the Ethernet port LED which is on the motherboard.

From reviewing other answers to similar questions on this site, I see that it might be the PSU, but I don't understand how it could fail immediately from overclocking - After the BIOS adjustment my son restarted the PC and then - nothing.

I'll get my son to try the strip down to essentials route suggested.
Power supplies can fail at the most importune times - a little extra draw, and some component can go, especially if it's not a good quality component.
Are you sure you cleared CMOS

Here is a failsafe procedure:

1
Remove powercable from PC

2
Push startup button to release current from capacitors.

3
Move jumper to clear position for 30 sec's

4
Move CMOS-jumper to normal position

5
Powercable reinsert

6
Power up


When raising the FSB you normally also increase the speed on AGP& PCI bus'es, so actually everything can suffer from this increased speed.

A good one by stockhes...can also try removing the CMOS battery for say an hour and putting it Back and power up the pc.

MD
Thanks for the tips. Tried the clearing CMOS routines, but nothing worked. In the end my son had to go out and buy a new motherboard and PSU. Still don't know what the failure was, but may get time to try different combinations now we have spares...
No comment has been added to this question in more than 21 days, so it is now classified as abandoned..
I will leave the following recommendation for this question in the Cleanup topic area:
PAQ/ refund

Any objections should be posted here in the next 4 days. After that time, the question will be closed.

Compfixer101
EE Cleanup Volunteer

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modulo

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