[SOLVED] What power rating of UPS should I get?

[creatip]

Hello everyone.

So I got an old system

• AMD FX6300 OC to 4.3Ghz
• Radeon RX570 (not 5700)
• PSU cooler master 500W
• UPS Prolink (dunno if it's an international brand or not) 650vac

So I OCed the cpu, and tuned the gpu to draw max power it wants. The weird thing is, when I run furmark to test the gpu, about 5 seconds in, my UPS was practically screaming with continuous and loud beep, and in about 2-3 seconds, everything shut downed, with the ups keep screaming. I have to manually turn off and turn on again the ups to reset it. This doesn't happen if I plug the power cable straight to the main, so I'm assuming the power draw is still within limit of the psu. So I don't get it, how does the 650vac ups not have enough juice to run a 500w psu? Is my ups just broken? It's fairly new, about 1 year or so.

Thank you.

Edit: I just found out that 650va is not the same as 650w, like I thought all this time (because volt-ampere equals watt). Just found out that 650va is about 390w, so no wonder it's screaming under stress load.

So my second question, aside from getting a bigger ups obviously, can I parallel the AC output of the ups to my main outlet? So the idea is, when the pc is under heavy load, the mains will lessen the ups load immensely. Crude idea, but will it work?

 

[Rogue Leader]

can I parallel the AC output of the ups to my main outlet? So the idea is, when the pc is under heavy load, the mains will lessen the ups load immensely. Crude idea, but will it work?

No, and this also sounds like an easy way to burn your house down.

Do it right or don't do it.

 

[creatip]

No, and this also sounds like an easy way to burn your house down.

Do it right or don't do it.

Hi thanks for the reply. Okay then, guess I have to browse for a higher rating ups.

Also from reading around, people always say go for a pure sinewave ups, instead of simulated sinewave (which costs a good percentage more than the same rating simulated sinewave counterpart). Now I understand about AC power being in a sinewave form (and DC is not), but what I don't get is, why is simulated sinewave bad for the psu?

 

[Rogue Leader]

Hi thanks for the reply. Okay then, guess I have to browse for a higher rating ups.

Also from reading around, people always say go for a pure sinewave ups, instead of simulated sinewave (which costs a good percentage more than the same rating simulated sinewave counterpart). Now I understand about AC power being in a sinewave form (and DC is not), but what I don't get is, why is simulated sinewave bad for the psu?

Its not that its bad, its that new Active PFC PSUs can often have sensitivity to non-pure sinewave power, and so when it switches to battery the system will actually shut off, kind of defeats the purpose. However there are some new models that don't have this problem, I'm not sure how they do it, but I purchased a model from APC for my wife's system thats not Pure Sinewave and it has no issues switching.

If you want a good deal on a pure sinewave UPS, look into Cyberpower. I run 3 of them and they have been excellent.

 

[creatip]

Its not that its bad, its that new Active PFC PSUs can often have sensitivity to non-pure sinewave power, and so when it switches to battery the system will actually shut off, kind of defeats the purpose. However there are some new models that don't have this problem, I'm not sure how they do it, but I purchased a model from APC for my wife's system thats not Pure Sinewave and it has no issues switching.

If you want a good deal on a pure sinewave UPS, look into Cyberpower. I run 3 of them and they have been excellent.

Hmmm if I didn't interpret it wrong, as long as the battery version of the AC output doesn't immediately shut down my psu, then I'm good? I was afraid that simulated sinewave would kill my psu slowly, or something.

 

[Rogue Leader]

Hmmm if I didn't interpret it wrong, as long as the battery version of the AC output doesn't immediately shut down my psu, then I'm good? I was afraid that simulated sinewave would kill my psu slowly, or something.

It won't damage your PSU, no. But if when switching from AC to battery power it causes your system to shut off, it defeats the purpose of a UPS.

 

[creatip]

It won't damage your PSU, no. But if when switching from AC to battery power it causes your system to shut off, it defeats the purpose of a UPS.

Ah okay. I know for sure the UPS I'm using now doesn't output pure sinewave. Just before I posted this, I tested unplugging the power cable of the UPS, and it beeped like expected, no shutdown on the PC. So I guess the new UPS I'm gonna get doesn't have to be pure sinewave then. I understand sinewave output is better, but in these time, every bucks I save is a blessing