it could have, but much more likely damaged the motherboard, as for the
psu it should be enough for your pc, although, from what i have found and read, the magna
psu is not very stable in the 12v rail, it drops below the 12v, so this *MAY* be your problem, or it could also be the motherboard. if you can borrow a
psu that is not a cheap, generic one and test it you should be able to determine whether it is that or the
mobo.
Just keep the
psu in mind for the next time you do a full overhaul, it is one of the most important, but most overlooked parts of the pc, just read a few reviews on the internet.
if it is the
mobo, you will need a new one, but i doubt that it would be, also, if you
psu has any type of surge protections it should have killed itself to save your pc so it may be damaged, but since your pc isnt failing i doubt that also, try a different
psu, or you could just buy one from a well known brand like thermaltake and antec, and just keep it for another upgrade anyway, even if it doesnt solve your problem
of course the solution is all up to you and depends on yourbudget, but i would recommend borrowing one first, or you could take it into a pc store, they should be able to look at it for you if you want to pay for the service
I would definately try the
psu first tough, because a replacement of the full
mobo, without looking for some second hand one, would require and almost full system upgrade
EDIT: sorry for the long post