[SOLVED] Uninterruptable Power Supply: Supplying 330W on a system that will likely demand 370W

Mister Lemons

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I feel kinda stupid for not actually researching this further before jumping on a purchase. I recently had a power outage that lasted no more than two literal seconds. My computer came out fine but my old junky server didn't. It was a PSU failure. Luckily, I had a spare.

It was that night I decided to buy a surge protective UPS to ensure my PC doesn't ever die from a lack of power and cause physical damage to its components. So I right quick calculated a basic power consumption for my rig, bought a 330W UPC, and here it sits with me hesitant to hook it up for one crucial reason; I don't think it's enough...

My calculations were based on max draw from my GPU, CPU, and average from a mid-range MoBo. I didn't bother to factor in the case fans, LED strips, monitor, or storage thinking it'd be negligible. I got the UPS and had to hook up the battery and thought "good lord this thing is small, it's gonna power my whole PC under load?". I feel like I already know the answer to this, but I gotta ask anyway cause I feel like some of my components simply will not be using an incredible amount of power (I.E. the board probably won't be using 70W).

So, my question is, what happens if my system attempts to use more power than can be supplied by the UPS? The thing is rated for 330W and is supposed to give me enough time to power down safely. That being said, I might be pushing max load when the power does cut out and that WILL be more than the thing can supply to a thirsty PSU. I'm not looking to actually USE the computer when its under power, but simply shut it down in the event of a power outage.

---Build is as follows---
Ryzen 5 3600 (65W)
Asus X470 Prime (70W?)
RX 580 (180W)
2x M.2 (14W?)
2x Trident Z
---Other Components---
6x Case fan +1CPU fan (~2W each)
3x LED strip
Corsair CX650M
Dell 27" LED monitor I'd like to hook up as well

I suppose another option is leaving the monitor off the battery and if the power goes out to just press the case power and put the system to sleep (as the button is set up to do). My only desire for the setup is to prevent damage to the system in the event of a power surge and/or outage.
 
Solution
First of all I think the odds of the power going out with you using full load is slim.
I would try it first at idle and see what happens.
I think it should work at idle.
Then I would increase the load and try it.
I think the worst that can happen is that it cuts out.
First of all I think the odds of the power going out with you using full load is slim.
I would try it first at idle and see what happens.
I think it should work at idle.
Then I would increase the load and try it.
I think the worst that can happen is that it cuts out.
 
Solution

Mister Lemons

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First of all I think the odds of the power going out with you using full load is slim.
I would try it first at idle and see what happens.
I think it should work at idle.
Then I would increase the load and try it.
I think the worst that can happen is that it cuts out.

This is what I want to do. I guess what I really want to know is the worst case scenario if I have the PC running and unplug the unit to simulate an outage. Is there a possibility of damage to my system or the unit?
 
This is what I want to do. I guess what I really want to know is the worst case scenario if I have the PC running and unplug the unit to simulate an outage. Is there a possibility of damage to my system or the unit?
I think it's a tough call.
I think if you are under full load.....and you cut power....and the PC isn't writing to any of the drives...I think you will probably be OK.
I think an issue might arise if a drive is being written to and the power is cut.
As far as cutting the power causing damage to the hardware...I think this would be rare.
 

Mister Lemons

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I think if you are under full load.....and you cut power....and the PC isn't writing to any of the drives...I think you will probably be OK.
I think an issue might arise if a drive is being written to and the power is cut.

That does answer a bit. If I'm altering the contents of a drive, then I'm not gaming or doing anything power intensive. I suppose option B is simply returning this unit and forking over a bit more for a higher-output battery.