UPS and Transformer Q need help!

Need Help_71

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I was wondering if this set-up would work:

1. Tranformer connected to socket (change 240V to 120V)
2. UPS connected to transformer
3. PC connected to UPS

Questions:
Will this work?
If not can you recommend a UPS which takes an input of 240V and supports 650-700W for MAX 5 mins? Preferred price = below 150 USD

Thank you :)
 

mathew7

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From where does the 650-700 figure come?
If it's from PSU, then you probably don't need that much.
My i5-2500 with AMD 5850 consumes around 270W max (tested under Skyrim). So unless you have 2 or more cards in crossfire/SLI, you will be pretty far from the 600W mark.

UPS-es usually specify how much power the inverter can handle (usually specified in VA, not W) and runtime at certain loads (which is related to the battery). So if you see a PSU rated at over 400W (600+VA) and 5mins at 200W, then at 400W it's expected to last 2.5mins.
 

mathew7

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But do you really need the transformer? I mean if you are in a country with 240V, why not buy a 240V UPS from the start? PC power supplies usually accept 120V and 240V, in the worst case with a switch.
If you already would have an UPS, then yes, transformer should be good. But when buying new equipment, you should not bother with transformers and buy according to country voltage.

And you still did not answer the 600W question: how did you get to that number?
 

Need Help_71

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Can you tell me what UPS is good for this build?

i5 2500k not OC yet
GTX 680
z77 Asrock MOBO
2XZ4BG Ram - G.Skill
Case - NZXT Phantom White
Western Digital Caviar Black 1 TB
OCZ 750W ATX12V Power Supply
Cooler Master 212 EVO

I dont need the UPS back-up for more than 4-5 mins :)
 

Need Help_71

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I tried finding them but I couldn't get many results and they're not readily available where I live :/
 

mathew7

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Anandtech's review seems to get 362W for a 680 + i7 3960X in Metro 2033. So for your quoted UPS, the "half load" time should be good.
 

Need Help_71

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ohh ok......I haven't bought the above stated build components yet. Do you think I'll be okay with a smaller PSU?

Another question, so a UPS that supports about 400-450W would be fine then?
 

mathew7

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It sould be fine. But regarding runtime, it's the battery capacity that gives it (watch the specified full and half runtimes, and be careful when comparing different UPSes with different wattage).
 

Need Help_71

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ok thanks alot!

Just to sum things up,

1. A transformer and UPS setup would work but UPS at 240V would be better.
2. Watch out for specified runtime.
3. A smaller PSU would be ok.

Is that right? :)

Thanks again
 

mathew7

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1. Should work (don't know if somebody actually use it)

3. PSU and UPS don't need to be matched. It's the actual HW that needs to be under the rated values for both. But it does not matter which is higher.