I just got a new Alienware computer. The power supply is 420 Watts. I plug my Computer, 22" monitor, and external hard drive into the APC. My external battery is an APC Back-UPS LS 700 (700VA/410W). Now here is the problem. When I do a self test on the APC the alarm goes off and the indicator light comes on showing me I need to replace the APC battery. Could it be that I'm drawing too much power for the APC to handle? My old computer, which had a 250 watt power supply, never set off any alarms. If I need a new APC, I'm looking to get the Back-UPS RS 1000VA (1000VA/600W) for an upgrade price of $167 or the Back-UPS RS 1500VA (1500VA/865W) for an upgrade price of $195. Any thoughts would be greatly appreciated. One last thing...my APC Back-UPS LS 700 is under 1 1/2 years old so the battery should still be good.