PSU/Mobo problems--Help!

neonleon79

Hi all
Built my new machine just over a month ago an all was rosey till last thurs. Switched on my ups an pushed my power button. Cue nasty 'fizzling' sound an dark smoke filling my case. Guessed it to be my psu which i thought to be and paid to be good. Brought it back an got a replacement (i was told it was new but i dont believe them, im in vietnam an customer service aint the best, it didn come in a box an i was suspect)
So, plugged in the replacement an powered on, everythin started but my keyboard wasn detected.

So it turns out all 6 of my usb ports are not working. My 4 usb 3 ports are.

Also, just had a BSOD while having device manager open (which says all my usb ports are working by the way) and opening chrome...

Obviously, somethin aint right

So, is this a mobo problem? hav i damaged it by frying the psu?
Could it still be a psu problem? when i plug in my portable hd it lights up, but nothing comes up!
Did my mild overclock do any damage?

My spec
CPU-i5-2500k @ 4Ghz 1.2V
Cooling-Thermalright Archon
Mobo-Asus P8P67 Pro Rev 3.0
GPU-Asus ENGTX 570 DCII
PSU-Corsair HX850
HDD-Samsung Spinpoint F3 1TB
Case-CM 690II advanced
UPS-Santek Blazer 1000V

Any an all help will be much appreciated.. need some answers as i need to try for a replacement something (mobo or psu) as soon as possible
Thanks