is it safe to power it up again to retrieve a cd?
Why not just shove a paperclip into the release hole of the CD drive and pull it out that way?
As to whether it safe to plug it in again, probably, but it wouldn't hurt to have a fire extinguisher handy.
How did this thread morph from my CPU blew up to, your PSU blew up? If the switch was set to the 115 Volt position and then the PSU was plugged into 230 VAC for a little while at least, the 12V rail was a 24 volt rail , and the board's voltage regulators were responsible for reducing it. (Yes, this is an oversimplification, but not a complete stretch). Not exactly a conducive environment for any component survival whatsoever.
The new Antec PSU (Earthwatt series anyway) are auto-switching with respect to input voltage, and perhaps many others, So, a supply with this feature couldn't do any damage whatsoever.
This post actually left me speechless and ROFL, but I've recovered now and I'm fine, thanks for asking.
He can try to get another PSU and see what happens, but based upon his really noob move at switching voltages under power even, I would recommend he have a professional install it - even though it is a simple job. Of course, there is no guarantee that the system will still work - but it's worth a shot. If he can borrow a PSU to test the system, that might be even better- but then again I recommend a pro do it as he didn't use rare sense. (It would be common sense if everyone had it.)
I think this bespeaks the need for manufacturers to rethink end user qualifications when in the design phase. It behooves them to strive to move beyond the rather mundane and commonplace fool proof, and into the eclectic realm of ***** proof. To be quite candid, I've owned a few things over the years that would have benefited from being so engineered. Oops!