UPS for PC Music Server


Do you use UPS for your music server? In case of power outtage, could your music server potentially sustain significant damage, hard drive failure, corrupted OS etc ?
I currently use passive power conditioner for my PC which I found to significantly improve the sound quality. However when I try to add UPS for my computer's protection, I find consumer computer grade UPS to degrade the sound significantly, dynamic is more compressed, sound stage also suffer significantly. I even tried those with true-online power which also did not help matter very much and some units even added more noise to the line.

2 possible solutions that I can find so far that should let me add UPS without degrading the sound (I hope) is PS Audio Powerpack 1500 or PurePower units. Have anybody tried these 2 units or have a chance to compare the two? PS Audio should be quite a bit cheaper so I am more interested in this unit. I only plan to use this for my computer music server only and plan to plug the unit into passive line conditioner first.
suteetat