comp not making POST

[Pyr0]

hey all,

my comp wont start all of sudden...
seen alot around on this but nothing very definitive

basically you turn the power on, fans run but the monitor shows no signal and the comp does not boot, there are no system beeps

tried several things including resetting the CMOS, and swapping components with another comp.
tried starting the machine with just fans and mobo connected, no CPU, RAM or graphics, no system beeps no-nothin, just the fans running.

from this i would conclude that the problem is the motherboard, but then i transfered the components from it to a working computer with a similar motherboard ie: i transfered CPU,RAM,and graphics. it ran fine which would also indicate motherboard failure of the first machine.

BUT>>> then i transfered all the components back into the second working machine, which now of course does not work... same problem as the first machine now, and i ran all the same tests as above with all the same results.
I'm unsure what to do as im positive the motherboards got somethin wrong with it (so probably both motherboards) but how did the second computer get damaged? it must have been a component from the first comp, the only different thing is the speed of the processor, the brand of RAM and the graphics card.

ummm dont think there were any surges or anything, dont think problem is related to the PSU (but it could be...)

first comp:
ASUS A8N SLi Deluxe
Athlon 3800 64 Processor - (single core one)
2 x 512 sticks
ASUS x850xt

second comp:
ASUS AV8-VN
Athlon 3200 cpu
2 x 512 sticks
x1900

cheers all

[SnowDog]

You've answered all the questions and come up with exactly the same conclusion I would: that something must have caused mobo 1 to fail, and now it has done it to mobo 2 after you put it in there.

Since you know what you are doing, forgive me asking this, but you did all the swapping with the power disconnected, didn't you?

What PCI/AGP components are involved? Can you list them?

[Pyr0]

lol.
I took all the parts into a store today, only to find they reached exactly the same conclusion that i did, both mobo's are dead. Although they wernt able to come to a proper conclusion as to the cause of the problems I suspect the original problem was a freak power spike from the psu, as it originally happened while the comp was on - which would have killed it.
As for computer 2.... yes i forgot to take out the power before swapping compnents... DOUH, so yeah, plugging in the PCI-E graphics card would have caused a spike stuffing mobo #2
Other than that everything is fine, all the other parts were declared fine, which is a relief.
I realised today after i bought the new mobo's that i forgot to disconnect the second one - o well, lesson well learnt, i wont forget that again.
Cheers SnowDog.