So I've built myself a new PC and its been up for about 2 weeks. This morning i wake up to the sounds of what seemed like M80's in my room however i knew from its direction it was my PC. Upon trying to turn it on (which failed) and testing (aka sniffing for what burned) it was def the PSU. Other notes are that i heard about 2 mini bangs then the big one which left my pc silent afterwards.

My Rig: Asus p5e motherboard (the one thats basically a stripped down maximus formula)
Intel e8400
2x2GB gskill ram
2 WD 640GB HDDs
Antec 900 with all of its tricool fans (the fans came with a message saying that the low setting was defective on some models however did not indicate that the fans would malfunction)
LG Bluray/HD-DVD rom and DVDburner
2x MSI branded ATI 4850's in crossfire
850 watt antec Truepower quattro PSU (http://www.newegg.com/Product/Product.aspx?Item=N82E16817371009)

Now my question is do you think the PSU was defective or do you think that any of the parts have problems which would lead to overloading the PSU? My guess is that it was just a bad PSU however maybe its possible that the asus p5e motherboard malfunctioned and overdrew or perhaps my house voltage spiked. Regardless i stole a rosewill PSU out of an old PC and it seems to be up and running with 1 GPU (didnt want to risk crossfire overdrawing on the PSU).

Was it plugged in a surge suppressor? Was there any power-related event like lightning/black-out?

It could have been defective, but I think perhaps it could have been a surge.

I always have my PCs (And 52" LCD TV :> ) on a UPS.
I generally get PSUs that also do power conditioning.

What they do is actually provide the power to the Units which ensures constant clean power.
If you get the lowest end UPS, the power comes from your house power and the UPS only kicks in when
it detects a spike, power loss, etc... However, there is the smallest of delays in this case which can still be harmful. (Not nearly has bad as unprotected however.)

Its on an old IBM branded surge protector, perhaps its not sufficient enough for this type of equipment however. I think I will get a UPS now that you've mentioned it. Thanks

Also can anyone recommend a decent cheap UPS i may be able to pick up at best buy?

I have used an APC UPS for years. In fact, I have two of them because i run multiple computers. Last I saw, Best Buy carried them. Before I got the first UPS, I had lots of troubles, but most have now disappeared.

APC is great.
Tripplite is great on the larger units.

I went from a Tripplite to an APC and currently running a Belkin(F6C1500-TW-RK who dropped their UPS line ) but that is my stupidity for leaving APC.

Triplite unit last me 4 years(double the warranty) and my APC 1000(big bulky server model) lasted me between 4 and 5 years and that was running 2 moderate machines 24/7 and a game rig.

I would highly recommend not just taking in the VA rating as it is misleading...read on the box and make sure you get enough watts to keep your gear running.

I never run my machines "naked" to the wall...always use a decent UPS with AVR...it is a minor investment compared to the $1000+ for a decent game rig.

APC would be the best if money is no object. They're not cheap.

2nd choice would be Belkin if money is tight.

You don't need one that's above your psu total wattage. Just enough time for a safe shutdown. APC can be controlled with built-in Windows driver from MS. Belkin has their own software called Bulldog that does shutdown, schedule, self-test, etc. Also displays the current load & condition of battery.

I ended up getting a cyberpower UPS with AVR since thats was the only one at best buy under 100. I should have bought an UPS years ago, thanks for the recommendations guys!