Cannot bootup/run with turbo switch on

[todd]

An old 486 boots up and runs fine (albeit slowly) if the turbo switch is OFF.

If the turbo switch is ON, the computer will not USUALLY start the POST/Memory Click, and there is no video at all in this case.

If the the turbo is ON and the computer does start the POST, there will be video, but the 486 will not go past the Memory Click Test.
It will just freeze, or sometimes restart and go into a loop, ad nauseum.

If I operate the computer with the turbo switch off, then turn the turbo on, the computer will freeze within a very short time.

What could be wrong?
Thanks for any help.

[tbhoover]

The switch wire may be plugged into the mobo wrong. Check the mobo manual for wiring diagram and take a peek into the case and see if it is in the right contacts. If you don't have the mobo manual, the mobo itself may be labled. Also, you can find many manuals on the web site of the manufacturers. 486 is pushing it though - it's ready for the museum.

[todd]

Thanks, but the pins all seem to be in the right place.
So, I don't think that's the problem.