Hi, I just installed a 2nd HD4890 on my system, so am running X-fire. Now something I did not foresee, my current UPS : APC 650VA only supports ~390W. At load I am almost pulling 550W+, and the APC 650VA is not supporting my system. Any good UPS, which I should pick up, I guess one with 1100VA should be good, which can support a throughput of ~650W-670W...???