Which UPS?

Ben643

Ben643

Ben643

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We keep having power cuts in our area recently for some reason so I'm looking to get a UPS. I just want to have enough time to save what I'm doing and shut the PC down (or having it done for me would be even better).

How would I go about finding which one I need?

I've been looking at this one but I assume it won't be powerful enough for what I need?
http://www.overclockers.co.uk/showproduct.php?prodid=UP-034-AP

Here's the spec of my system.

Abit IP35 Pro Motherboard
Intel Q6600 Quad Core
4GB (4x1GB) OCZ PC-8500 RAM
OcUK GeForce 8800 GT 512MB GDDR3 HDTV/DVI (PCI-Express)
and I *think* my power supply was an Enermax Noisetaker 535W
 
Your machine is going to be pulling approx. 300+ Watts from the mains and that UPS is only rated to 240 Watts.

There's a UPS finder on the APC site that allows you to enter your machine details, required runtime etc. that's worth a look.

When your comparing make sure you check the rated output power in Watts rather than going by the VA rating. You're probably going to be looking at something around 700 VA which is approx 400 Watts.

If you want to keep the screen running don't forget to factor in the additional load.
 
bremen1874 said:
Your machine is going to be pulling approx. 300+ Watts from the mains and that UPS is only rated to 240 Watts.

There's a UPS finder on the APC site that allows you to enter your machine details, required runtime etc. that's worth a look.

When your comparing make sure you check the rated output power in Watts rather than going by the VA rating. You're probably going to be looking at something around 700 VA which is approx 400 Watts.

If you want to keep the screen running don't forget to factor in the additional load.
Click to expand...

At idle, his system won't be drawing that much, imho it'll probably be less than 200W, if all he's doing is saving stuff.
 
If you can guarantee that the machine will be at idle when the power cut hits then that's fine.

If the machine happens to be pulling more than 240 Watts when the power cut happens then there's a good chance that the UPS will just cut the power when it detects the overload condition.
 
You have to multiply VA-rating by 0,6 for getting actual power rating.

PC with those parts could peak somewhere around 200-220W and after that there's losses in PSU. IIRC that Enermax noisemaker is rather oldish by todays standards so if we assume below 80% efficiency that would make ~260W peak for PC, then about 70W would be enough for any up to 24" monitor and we would have 330W peak consumption.
For light desktop use that UPS would be enough but it surely can't power max draw for long time. (cheaper UPSes probably don't handle momentary overloads as well as higher end UPSes)
So I would keep 550VA model as lot more reasonable choise.
 
Basically, if there is a power cut, and the software starts shutting down the comp., if the comp. PSU draws more power than the UPS can supply (or is rated at), the computer will simply reboot, and fail to shutdown properly, which I found out from my own experience.

Better to spend a bit more (if required) and get a UPS up to the task of dealing with the power draw of your comp..
 
Cheers guys, that's been a massive help. Think I'll just go for the 700VA one, I had planned to spend about £100 on one anyway.

Hopefully it'll be back in stock soon.
 
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