A while ago my 350W PSU failed so I replaced it with an Antec truepower trio 550W.
I connected it to my Asus M3A motherboard and when I turned it on, sparks came out of that motherboard.
The motherboard is wasted, and I was told that something with CPU voltages went wrong, I don't really understand, but anyhow, I need to get a new motherboard.
I want it to either be compatible with the 550W PSU and my Athlon 64 X2 dual core 6400+ (because somehow, that's where it went wrong).
If you say it's silly to buy a new motherboard and not a new CPU, which ones should I buy, that are compatible with eachother, my PSU, my memory (I really don't have a clue what type or RAM it is, I could check if you want).
I really need some help with this, I want to avoid another "fireworks party", and need my PC up and running again soon.
There is a very good chance that, originally, either the motherboard failed and took out the PSU or vice versa.
Having said that, I wouldn't just plug the Antec PSU into another motherboard without doing a little testing first.
Try to verify (as well as you can) that the PSU works. If you have a multimeter, you can do a rough checkout of a PSU using the "paper clip trick". You plug the bare PSU into the wall. Insert a paper clip into the green wire pin and one of the black wire pins beside it. That's how the case power switch works. It applies a ground to the green wire. Turn on the PSU and the fan should spin up. If it doesn't, the PSU is dead. If you have a multimeter, you can check all the outputs. Yellow wires should be 12 volts, red 5 volts, orange 3.3 volts, blue wire -12 volts, purple wire is the 5 volt standby. The gray wire is really important. It sends a control signal called something like "PowerOK" from the PSU to the motherboard. It should go from 0 volts to about 5 volts within a half second of pressing the case power switch. If you do not have this signal, your computer will not boot. The tolerances should be +/- 5%. If not, the PSU is bad.
I own an Antec 550 TP3 and it's a pretty good power supply, but I suspect you may have a problem with yours. About the only way you are going to get arcs 'n sparks from a motherboard is if the PSU protection circuits do not electronically shut the PSU down.