Usually you see two ratings advertised, but they really should include another.  Ad copy will generally cite VA (volt-amperes;  a measure of battery capacity) and W (Watts, a measure of the power the UPS can feed to computer[s]).  Traci may have been zapped while using a surge suppressor strip because those are notorious for having insufficient surge capacity.  Some ad copy will also include how many Joules the unit is rated for;  this is a measure of how much spike energy the unit can absorb.

     I fully agree that you can't have too much.  Because of the price/capacity curve, I would say that even for a PC with a 650w power supply, I would get a 900w UPS.  You can also feed/protect the monitor with it.  Most UPS units have a pair of Cat6 jacks, so you can run your internet Cat cable from your modem/router into the UPS, then another CAT cable from the UPS to your computer.

     Also consider the weight of the UPS, and factor in your own physical ability to heft things and whether you'll need to carry it upstairs. Some of the bigger capacity units come broken up into two chassis which you connect once they're in place.  I also like units with an LCD voltage display which can be rotated 90' to allow for either tower position or rack-mount position.

     If you have two or three PCs, you might compare prices to decide whether to get two/three modest UPS units or one big unit.  My last "event" was a meltdown of a utility pole transformer which fed my house and several others.  The weird brownout low voltage event destroyed one of my two-box UPS units.  I replaced it with an APC SMT2200 rated for 1980w power output, 2200VA battery capacity, 530 Joules surge energy suppression, and 112lbs weight (I grunted considerably getting this upstairs!)

     This only feeds one workstation, Galadriel, but Galadriel has two liquid-cooled processors and a 1,350w internal power supply, and the UPS also feeds Galadriel's two 30" 2560x1600 monitors, 150w each.  Galadriel doesn't use all of her 1,350w;  she pulls about 770w when rendering at 100% CPU.  But with PC internal power supplies -as with external batt/surge UPS- it's good to have more capacity than needed.  Everything lives longer if it isn't running at the ragged edge of its ability.

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