Odd power question

[DevilMan]

My parents computer was on the fritz here is while back where it would not turn on. They replaced the power supply but still had the same problem, comp would get a small burst of power then not boot.

They took it back to where they bought it, local Computer store, and they found it was the motherboard. So they swapped it out for a new one.

Now the problem is the mouse and keyboard do not come on when the PC is booted up. BUT when they turn off the computer the mouse light turns on and the keyboard lights light up. Turn the system back on and they turn off and are unworkable.

Could this be a faulty mobo? I cannot think of any other reason that would cause them to behave the way they are.

 

[DatHak512]

if you have any other mice, or keyboards, i'd try those, or just try the mice+kybd combo on another system, if you have access to one. from what i understand, the mice work (or blink i mean) right as the comptuer turns off? that kinda sounds like the MOBO, but i guess it really could be anything. check em though, just to be sure...

 

[Vertigo Acid]

Sounds to me like the +5vsb is working great, but the PSU or mobo is having issues with the regular +5vdc rail.