UPS: Help with capacity decision

[BishamonX]

I've been getting random power outages lately so I decided to get a new UPS for my desktop. I already have a UPS for my NAS drives (2x Synology DS212j and 1x MyBookLive 1TB), an APC Back-UPS 650VA, which outputs 400 watts.

 

I can't figure out if I should get a UPS based on my PSU or based on the actual usage of my desktop/monitor. I have a Thermaltake 700 watts PSU, but I only got it to handle any type of upgrades I might throw at my PC.

 

My computer specs:

CPU: Intel Core i7-3770K

GPU: Asus GTX 660 Ti 2048MB

RAM: 16 GB Corsair Vengeance 1600 MHz

Motherboard: Asus P8Z77-V Pro

CPU Cooler: Corsair H80i

HDD: 2x WD 500 GB

Optical: LG DVD R/W

Monitor: LG Full HD 24"

Fans: 4 120MM fans (+2 soon, so 6 total)

 

Soon I'll add a Samsung 840 Pro SSD as my boot drive.

 

The watts usage for my specs (guess/estimate) would be no more than 600W + whatever the monitor needs which I think is not much.

 

I only need it to be able to shutdown safely, and if I'm not actually near the PC, the software would shutdown the computer for me (love APC for that).

 

Any suggestions would be greatly appreciated.

 

Note: Apologies if this was posted in the wrong forum, I didn't see a UPS forum, the "Cases and Power Supplies" was um, well, almost what I wanted to ask about.

[Godlygamer23]

I'd make it handle power based on your PSU or perhaps further.

[Andi]

your system with monitor needs maybe 300-350W under load.

 

your APC Back-UPS 650VA could handle your pc fine. Don't forget that in idle your watt usage is very little. maby 50W-120W with monitor.

 

you could take your UPS, plug your pc in it and look if it will run, i'm 100% it will be no problem.

[Rhotis]

You are using roughly 380 watts at 90% load without the monitor.  Calculate from there.  Chances are you wont be utilizing 90% of your resources at any given moment.  

[Godlygamer23]

You are using roughly 380 watts at 90% load without the monitor.  Calculate from there.  Chances are you wont be utilizing 90% of your resources at any given moment.  

You also don't want to stretch the limits of your resources too far either.

[Electronics Wizardy]

I suggest you buy a power meter and then measure how much power your system actually uses and then add 25 to 50 percent.

i suggest one of these http://www.p3international.com/products/p4400.html

 

of use a multimeter but be careful.

[BishamonX]

Terribly sorry for taking so long to reply, I did exactly as Electronics Wizardy suggested, and the results were almost exact as Andi's response. At first, I tested my UPS with both case and monitor, the autoshutdown feature worked flawlessly which at this point I thought why use extra watts on the monitor, which was about 30 watts.

 

Currently only my PC (Case) is plugged in to the UPS and it shuts down automatically whenever there is power outage.

 

However, my NAS drives were without a UPS, did a tiny bit of info digging, DS212j uses about 18 watts, have two of those and of course connecting the router as well, so I ended up plugging them in an APC Back-UPS 350 230V which has a capacity of 230 watts output, more than enough, especially since both my NAS drives autoshutdown on power failures.

 

Just wanted to thank you guys again for all the help, really appreciate it.