Quiet UPS/power conditioner for HTPC?

[bigforearms]

Does such a thing exist? I'm going to great lengths to make my HTPC quiet, and I thought I'd get a power conditioner or voltage regulator to extend the life of my lcd monitor (125w rating) and HTPC (450w psu, but I don't think my build will peak more than 320w). I don't really care about up-time because this is for an entertainment system, I just want something to protect against crappy power that will be very quiet or preferably silent during normal operation.

Any suggestions are appreciated.

 

[Sycraft]

Normally most UPSes are totally silent. This is because consumer UPSes aren't actual real UPS (uninterruptible power supplies) they are SPS (switching power supplies). Their inverter and such are off normally, they cut line power straight through to the device and run a DC trickle charger off it, which makes no noise. However when they power fails they quickly switch over to battery output and that's when they make noise. So no noise, unless the power goes out.

Also, if you just get a power conditioner like a Furman unit or something it won't make any noise. It won't do power during failures though, it just regulates the input.