Bootup Problems

[Ludwig]

Hi everyone,this is my 1st post, I'm hoping someone can help
When I try to power up my PC after its been off for a while(o/night etc)so its cold, it starts for 1-5 secs then drops into standby.
If I keep trying, especially it seems if I turn it on its side it finally boots & runs perfectly, this sometimes takes 10 times.
Its an ATX, AMD1.1GHz, Asus A7v m/b.
I checked some voltages-
Power Good- off when pc is off, on when started( what I expected)
Standby- Always on
Power on- on when pc is off, off at startup( opposite to what I expected)
All the above are just over 5v
I thought that when the button was hit the p/s would start, give a "power good" signal then the m/b would turn on the "power on" signal
I'm assuming the problem can be the m/b not giving the signal to turn on or its the p/s not turning on,but I can't work out which
Any ideas anyone?

Thanx for any advice!!
Ludwig

[Rick]

The Idea that turning it on it’s side may be a clue to another possibility
A fan may be bad or going bad
By turn it on it’s side the fan sits on the spindle differently
Allowing it to spin freely and allowing the system to boot

In your Bios you should have a fan monitor
check the fan speeds for the correct rotation speed once you get it booted
That is IF you fans are plugged into the mother board with the 3 wire connectors

[Budfred]

It also could be a loose connection that is getting connected better in a different position. Check all cable connections to make sure nothing is loose.