Is the simulated or pure sine wave UPS suitable for the Corsair rm850x PSU powered system?
Is the simulated or pure sine wave UPS suitable for the Corsair rm850x PSU powered system?
Experienced through several recent power interruptions while working and gaming, I decided to invest in a UPS to protect my design files or prevent my PC from shutting down abruptly. I purchased a basic simulated sine wave UPS from Amazon for my system. After further investigation, I discovered it might not be compatible with my PSU. However, opinions vary—searching forums, the Corsairs website, and other sources revealed conflicting information about whether this UPS would work with an APFC PSU. I reached out to others seeking advice on this matter.
In my view, every personal computer should include a UPS.
UPS devices can generate three distinct types of waveform:
1. Square wave – the most affordable option. Suitable only for very durable equipment such as generators and motors.
2. Simulated sine wave (also known as stepped-approximated sine wave) – moderate cost. Ideal for most household appliances like refrigerators, washing machines, and lighting systems.
3. True/pure sine wave – premium price. Matches the output from a standard wall socket. Only suitable for delicate electronics such as medical devices, televisions, and PC power supplies.
Therefore, to safeguard your PC, you should opt for a true/pure sine wave UPS. Simulated sine wave models may still function, but they might not be reliable. Further details are available below;
When selecting a UPS, consider these aspects:
1. Waveform output (square wave, simulated sine wave, and true/pure sine wave)
2. Design type (stand-by, line-interactive, online)
From this information you can explore the differences in waveform and design.
https://suvastika.com/why-choose-a-sinew...erter-ups/
And here are insights on UPS design,
https://www.eetimes.com/document.asp?doc_id=1272971
Understanding waveform and design
For PCs, a line-interactive UPS is generally sufficient because power supplies can manage the 2ms to 5ms transition time easily.
Regarding waveform, a true/pure sine wave UPS is optimal. Simulated sine wave models are cheaper but not compatible with PSUs that have Active PFC. You might encounter problems if you use a simulated sine wave UPS with an Active PFC power supply. Here’s what happens, how it occurs, and why.
How do you identify which PSUs have Active PFC and which don’t?
It’s straightforward: any PSU certified at 80+ (such as 80+ Bronze or 80+ Gold) must feature Active PFC.
What is Active PFC?
Further reading:
https://en.wikipedia.org/wiki/Power_fact...near_loads
Potential issues with simulated sine wave UPS using Active PFC PSUs:
When a simulated sine wave UPS transitions to battery power, three possible outcomes arise:
1. The UPS signals an error and forces the PC to shut down instantly.
2. The PC shuts down immediately.
3. The UPS switches to battery, causing the PC to power off while remaining on.
Why does this occur?
Simulated sine wave UPSes generate a zero output during phase changes, creating a power “gap.” This interruption can trigger shutdowns in active PFC PSUs when switching from AC to simulated sine wave.
What should you do next?
As mentioned, your PC can operate on a simulated sine wave UPS, but be ready for possible complications. If issues emerge, consider replacing the simulated sine wave model with a true/pure sine wave UPS or choosing one immediately.
Power requirements
When it comes to power consumption, assess your PC and monitor’s draw. Don’t forget speakers and Wi-Fi routers if you plan to connect them to the UPS as well. Printers, scanners, and similar devices are excluded from the UPS connection since their startup power demands exceed what a UPS can manage, risking damage.
Setting a baseline for PSU wattage is wise—it provides extra capacity and extends runtime. With an 850W PSU, adding one monitor (typically 23W–52W) is reasonable. Wi-Fi routers use minimal power; for example, a Cisco modem at 12V and 3A consumes 36W.
Recommended UPS brands include CyberPower, TrippLite, and APC. These are among the top choices available.
Remember: A more powerful UPS ensures longer battery life and better protection for your PC.
To provide a suitable recommendation, I need to know your monitor model or part number, plus any other hardware you intend to connect. Additionally, your location (e.g., USA, Germany, Italy, Australia) is important so I can suggest models compatible with your power outlets.
Hello, thank you for your thoughtful response. The information provided is quite helpful. I’m based in the US and currently own an LG 32-inch 2K 165Hz ultra gear monitor as my primary display. My secondary setup includes an older MSI Optix AG32CQ 2K at 144Hz, which isn’t as critical and seems to be facing capacitor problems. All of these devices would ideally be powered by a UPS. I’m aiming for about 10 to 20 minutes of buffer time during any outage. Based on my PC’s power consumption, I estimate around 600 watts maximum. Right now I have a 5800X3D in the CPU slot for gaming, but switch it to a Ryzen 9 3900X for work; surprisingly, both use similar power under load. For reference, here’s the build information:
CPU
AMD Ryzen 7 5800X3D
RAM
64.0GB Dual-Channel DDR4 @ 1799MHz (16-19-19-39)
Motherboard
ASUSTeK COMPUTER INC. ROG CROSSHAIR VIII HERO (WI-FI) (AM4) 3
Graphics
LG ULTRAGEAR (2560x1440@165Hz)
Optix AG32CQ (2560x1440@144Hz)
4087MB NVIDIA GeForce RTX 4080 (MSI)
Storage
953GB NVMe INTEL SSDPEKNW010T8 (Unknown – SSD)
1863GB Samsung SSD 980 PRO 2TB (Unknown – SSD)
2794GB Seagate ST3000DM 008-2DM166 SATA Disk Device (SATA )
3726GB Seagate ST4000DM 004-2CV104 SATA Disk Device (SATA )
If you go with 600W/~1000VA UPS, then you're looking ~3 min runtime.
With your budget - doesn't happen.
E.g solid UPS (more than enough for your build);
Cyberpower CP1500PFCLCDTAA, 1500VA/1000W, line-interactive, true/pure sine wave,
specs:
https://www.cyberpowersystems.com/produc...pfclcdtaa/
amazon:
https://www.amazon.com/CyberPower-CP1500...B008U4SBVS
It costs ~$320 but currently on sale on amazon for ~$277. So, over your budget. And if you look the Runtime chart, then you can see that on 600W load, you'll get 7 mins of runtime.
Now, to get 20mins runtime for 600W load, you're looking towards much beefier UPS, e.g:
Cyberpower OR2200PFCRT2U, 2500VA/1540W, line-interactive, true/pure sine wave, rackmount,
specs:
https://www.cyberpowersystems.com/produc...00pfcrt2u/
amazon:
https://www.amazon.com/CyberPower-OR2200...JAHW0?th=1
Easy 19mins runtime on 600W load, but it will cost you nice $669.
Either mount it into server rack (since it's 2U) or as a tower (should include standing legs).
Though, it seems that you've underestimated the cost of a proper, good quality UPS. Since UPS'es job is to keep your PC running when there's blackout by supplying good and stable electricity to your PC, they also cost a lot of money.
For example, i payed €230 Euros for one of my CyberPower CP1300EPFCLCD (1300VA/780W, true/pure sine wave, line-interactive) UPS and i have two of them in use, one for Skylake build and another for Haswell build (full specs with pics in my sig). That makes $265 USD per one UPS, while your budget is $250 USD.
Since your PC is expensive, it's not easily replaced. Like it or not, if you want the protection, it's not going to be cheap. Though, if you want cheap and good UPS, you need to buy 2x UPSes; 1st the cheap one and 2nd the good one.
So, i advise you to buy good UPS this time around, since you already bought the cheap one.
Though, UPS'es idea (line-interactive topology) is to sustain PC as long as you can save your work and then shut down the PC safely. Usually 5mins is good. Maybe even 10mins.
But UPS is not a battery pack that you can run your PC off at all times. If you want that, buy a gasoline/diesel powered electric generator that provides you electricity when main electricity is off OR online UPS (either double-conversion or delta-conversion topology).
Online UPSes are used to back up entire server parks since online UPS topology is such, where power is constantly taken from the UPS battery and mains is used to recharge the battery. So, when main electricity cuts off, there is 0 transfer time. Only battery level is starting to drain. Downside is, that since battery is in constant use, it wears out more quickly. But online UPSes have several batteries, so, when one fails, the failed one can be replaced without ever cutting the power source to the servers. Oh, and also the fact that online UPSes are maintained by the tech you call on-site. Online UPSes are not user-serviceable (like line-interactive UPSes are).
Certainly a pure sine wave is always optimal. A simulated sign wave won’t pose any problems with most equipment. Remember you’re only operating for short periods on the simulated wave. During longer durations, power from the city simply passes through without issues. If you relied on a generator for extended periods, it becomes a bigger concern. Inverter generators are generally more costly. High-efficiency PC power supplies demand very clean electricity; otherwise, excess power is lost as heat inside the supply. The amount of power drawn affects the risk—using dirty power for too long can harm equipment. A UPS is ideal for brief outages where lights switch on and off quickly, such as when the power cuts for seconds. For longer durations, devices that run on solar are better suited. These systems convert DC to AC continuously 24/7. I own an older, large UPS with less than clean output. It only powers my ISP router for hours, keeping Wi-Fi available for my phone. During the last outage it lasted about 11 hours, but it damaged the batteries, forcing me to purchase nearly $200 worth of replacements. Running such devices outside their intended usage seems risky.
Everything outside of sensitive electronics is acceptable.
The PC's PSU is treated as sensitive electronics, and I wouldn't run a simulated sine wave UPS there—this issue has already been discussed.
I think it's important to draw a line here, because solar panels are also seen as generators but they produce DC, which gets converted to AC via an inverter.
Gasoline or diesel generators usually provide square wave output. There are both simulated sine wave and genuine pure sine wave versions available. However, just like the true/sine wave UPS models, these are more expensive than square wave or simulated sine wave generators.
I can clearly explain the reasoning behind the $50 price hike. Originally, befreo was coming in at around $250, which was in the 300s. I was estimating how much I’d need to spend to safeguard my PC from brownouts and estimated that about 10% would be sufficient. I rushed into buying the simulated sine wave before conducting proper research. Now I plan to use the credit for this purchase and acquire the Cyberpower CP1500PFCLCDTAA, a 1500VA/1000W line-interactive, true/pure sine wave as you suggested. A 5-7 minute session should be enough time to save work and power down my machine most of the time. When I mentioned 10-20 minutes, I didn’t grasp how much it would cost.