If I accidentally made a cap on a PSU go off...

would the mobo likely be dead? This happend to my xbox and both systems work in basically the same way. I accidentally hit the cap with a wire and there was a giant spark. Luckily nothing else was plugged into the PSU, except the mobo.
Thanks.

Unless you ruptured the casing with the spark, the capacitor itself should be OK. If it was a low-voltage cap then I shouldn't think that anything is dead.

Was the cap on the high side or the low side? High side cap = 120V into the low voltage side