UPS For Two Computers

[Owlieowl]

I'm buying a new UPS for our new setup. Our systems are as follows:

PC 1:
LED Monitor
i7 960 Stock
HD 7970 Reference Edition
Corsair 12GB Triple-Channel DDR3 RAM
3 7200 RPM SATA Drives, 2 in RAID
1 Crucial MX100 SSD
Xonar DX Sound Card
P6X58D Premium
AX860 PSU

PC 2:
CCFL TV as Monitor
i5 4690 Stock
R9 290
8GB Dual Channel DDR3
1 7200 RPM Sata Drive
Some budget ASRock motherboard (not my PC, I forget, shouldn't matter)
XFX TS 550 PSU

My estimate is that both PCs + monitors would pull about 600W combined at 100% load - maybe a bit less. Based on that, I believe this would be sufficient (850VA version)


Would anyone suggest I step up to the 1350VA one, or should the 850VA keep both PCs on for a couple minutes?

(edited to add in CPU information)

 

[GhislainG]

850VA is good enough as long as all equipment draws no more than 500W when a power outage occurs; otherwise the UPS will simply shut down to protect itself. I presume you took into account that a PSUs is not 100% efficient.

 

[synphul]

Without knowing the exact load of everything on both pc's, including the monitors (you have to factor monitor draw in as well) the best advice I can give is to try using a device like this kill-a-watt.

http://www.newegg.com/Product/Product.aspx?Item=N82E16882715001&nm_mc=KNC-GoogleAdwords-PC&cm_mmc=KNC-GoogleAdwords-PC-_-pla-_-Home+Gadgets-_-N82E16882715001&gclid=CjwKEAiAgfymBRCEhpTR8NXpx1USJAAV0dQyiN9jBie1xXNdaPO75Yl2iTSIXRZV3rzGdvlbq4Em5BoC98_w_wcB&gclsrc=aw.ds

Plug it in between the power outlet and your pc tower, try running some intensive tasks like gaming or something on it that will put the cpu and gpu under heavy load and see what the reading is. Same for the other machine. Do the same for both monitors, then add up the values to get a realistic load draw. Once you have that figure, then you can look at ups units and be sure to look for the table showing how much time they give at what power loads. (For instance, a 600w ups supplying 500w of power may only have 1.5-2min of battery life.)

It will give you a much more realistic idea rather than just guessing or theorizing on paper and the units are pretty affordable at $20. It may save you from spending a lot more on the larger 1350va unit if it's not necessary or could save you from buying twice if the smaller one isn't sufficient.

 

[GhislainG]

Between the 850VA and the 1350VA, there's a 1000VA that definitely will be powerful enough, even once the batteries get weaker in a couple years.

 

[Owlieowl]

I went for the 1350VA so I don't have to worry about it. I wanted to test the wattage but that's a $20 thing I'll probably never use again. Gets me two USB ports as well. Thanks for the advice.

 

[GhislainG]

It's a good decision. I own a Smart-UPS 1000 and a Smart-UPS 1500 (both bought used) that most of the time are running at 25-40% of their rated output, but I know they will last for a long time. The newest one was manufactured in 2007. Two failed in the past, but they were like 15 years old (and they were free).