[scrapper400]

Hi there,

On the DC powersupply for the PC at the back of my VM1, there are 5 LEDS. The correspond (from left to right) to +12V, -12V, -5V+5V and +3.5V.
The middle LED on my machine is not lighting up. On the top right hand side of the motherboard are five screw terminals. The one marked -5V is actually reading +3V.
Can anyone check the back of their machine for me and tell me whether they have 4 or 5 LEDs lighting.
My machine is throwing up multiple errors and I'm trying to isolate if it is a feedback error.

Help

[bloke]

I don't think that is your problem. Did you check the CPU for bulging capacitors? The power supply can be measured on the little board on the side of the card rack. Find the little test points - on a machine the age of yours, there should be five.
The one on it's own is 0v and the next four are -12v, 5v, 12v and 24v in that order.
Check them on DC volts to make sure they are in spec and then check on AC volts to see if there is noise on any of them.
Make sure that the fan is running on your CPU.

[scrapper400]

[QUOTE=bloke;1230008]I don't think that is your problem. Did you check the CPU for bulging capacitors? QUOTE]

Hi Bloke,
We found the problem in the end. Well it's been running all week and no errors since. The problem was with one of the lower DC IO boards at the base of the cabinet. The screwed in type. Reseating seems to have sorted it.

Cheers for all the help and suggestions.

Tim.