Question Is an APC 1100va UPS enough for a 1000w PSU ?

[manickraj]

Hi guys I'm wondering whether my APC 1100 ups be enough for a 1000 or 1050w psu. the expected PC build is:
Ryzen 7 7700X(AIO cooled) ,
RTX 3090
32 GB RAM
2TB NVMe SSD
and expecting 4 to 5 case fans.

Is a 1000w PSU overkill or not for this build (along with the above UPS question) ?

 

[Ralston18]

Most UPS manufacturers provide some sort of "calculator" to help determine the appropriate UPS wattage.

However, those calculators tend to lean towards higher end/more expensive units. And features that may not really be required.

I.e., bias being more wattage, more time, and "little value added" features.

Generally the UPS only needs to support the PC, the monitor, and perhaps some independently powered backup device.

Remember that the overall purpose of the UPS is to simply allow enough time to invoke a graceful shutdown for the supported computer. Just a few minutes.

Not to continue gaming, working, watching, streaming, etc... All of which are likely moot anyway if the power is off and the network is down.

A graceful shutdown being necessary for Windows to do some "housekeeping" (saving files and data) and otherwise prepare for the next startup. Unexpected shutdowns often lead to corrupted system files, configuration issues, and data loss.

If you are constantly at your computer and can initiate a shutdown when power goes off or otherwise becomes problematic then you probably only need a couple of minutes to initiate the normal Windows shutdown process.

If you are just as likely to be away from the computer there is also a likely need for a bit of extra time for you to return and initiate the shutdown. Again not much more than a few extra minutes.

Just my thoughts on the matter.

 

[bill001g]

This is a messy question. First it depends on how much power your pc really pulls not how large the power supply is.

UPS has 2 numbers that are related but not the same. The VA number and the watts number. I forget exactly what is the technical difference even though are in many ways the same.
What you tend to find is the VA number is much larger than the maximum watts. For example you commonly see 1300VA UPS that can only do 800watts.

You tend to have to go to 1500VA units to get ones rated for 1000 watts.

This is called read the specs. Some very expensive commercial UPS the VA number and watts number are the same.

What you also need to be careful of is you need true sign wave UPS when you are running high end power supplies. This is because new power supplies trying to be very efficient need very clean power coming in. Since you tend to not run very long on a UPS it is hard to say how much damage cheaper UPS do to your power supply. Some power supplies will just turn off if the power is not good enough.

So your first goal is to try to find out how much power you are really using and what you think the maximum spike might be. Does your current UPS show you the actual power usage. You can get a small device called a killawat that can give you a good idea. There are generic versions of this device much cheaper on amazon.

 

[Misgar]

True sine wave vs stepped (simulated sine wave):-
https://blog.tripplite.com/pure-sine-wave-vs-modified-sine-wave-explained

VA vs Watt ratings explained:
https://www.apc.com/us/en/solutions/industry-insights/watts-vs-va-whats-difference-anyway.jsp

UPS Buying guides
https://www.apc.com/uk/en/support/p...ide-for-selecting-a-battery-backup-system.jsp
https://www.cyberpowersystems.com/blog/buying-guides/choosing-a-ups/

Since you're probably not going to pull more than roughly 600W with the new RTX 3090/7700 build, your existing APC 100 UPS should provide 2 to 3 minutes shut down time, if the batteries are still healthy. Not much use if you're in the middle of a 10-hour render, but OK if you're doing something else.