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Is 800W PSU good enough with these specs?

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Is the 800W good enough for this?
 
I feel like I've seen 850w suggest for use with a 3090, so you're right about there, so if budget allows, a 1000w would be better. In a couple of W1zz's reviews, some cards had a bios that allowed the cards to reach near 500w themselves.
 
800W is way more than you need so, sorry but 1000W would be overkill.

See this: https://outervision.com/b/Gb1kpB

Note your liquid kit is not listed but I think the Enermax would have similar demands.

Note that no calculator wants to recommend a PSU that is underpowered so they all pad the results, some more than others. The eXtreme OuterVision calculator is and can be the most conservative for 2 main reasons. (1) They have a team of researchers on staff constantly researching components for us to keep their extensive databases accurate and current. And (2), it is the most flexible and has the most extensive databases of available options you can enter. This allows it to factor in all possible components to accurately calculate our needs rather than guess.
 
The recommended PSU for the RTX 3090 is 750W - and that should be a high quality 750w but that's when coupled with an I5/I7 it jumps to 850W recommended for an I9 paring with an RTX 3090. My recommendation would be a nice 850W you will want a bit of extra headroom when your I9 starts to draw a lot of power under load and you will want your rails steady and the less ripple you have the better. My rule is very clean power and about a 10-15% headroom.
 
on paper a 800w should be fine but i would be more happy with a 1000w its better to have too much than not. 50w over recon isnt a lot to play with.
 
If it's a high quality unit 850w for sure should be enough but I'd feel much better with a 1000w in that system
 
on paper a 800w should be fine but i would be more happy with a 1000w its better to have too much than not. 50w over recon isnt a lot to play with.
Especially if one plans to overclock then one will need more.
 
depends.
a high end 650w PSU can run a system just fine where a lower tier 850W PSU just shuts off.


i wouldn't OC anything in that PC tbh.
 
During gaming, you will never peak both CPU and GPU, most CPUs sit at 80-120 watts during gaming.

850-1000 watts yeah
 
There is no such thing as overkill when it comes to PSUs, no one can predict what some else is doing with their system. With a 3090, it sure isnt just to play browser games and surf the internet, but if someone dabbles in overclocking that extra headroom wattage just might be enough to keep from frying something.
 
Really need the model to say whether it's good or not. For all we know it could be 800w peak (not continuous). Doesn't say anything about the voltage regulation either.
 
Majority of PSUs work best around 50-75% load, try to calculate how much you will on average pull and then apply that to PSU. Basically your average should be within 40-60% of PSU and ofc peak shouldnt go over what PSU can do.

PSU is one thing I never save money on. Learned that from others that learned hard way.
 
Majority of PSUs work best around 50-75% load
This statement can be misleading. There is nothing to suggest a PSU operating in that 50 - 75% load range will be more stable, provide better regulation, better ripple suppression, better hold-up times, etc. than a PSU operating outside that range.

What is true, as a general rule, is that power supplies operating in that range tend to operate most efficiently - that is, fewer watts are wasted in the form of heat. But every PSU is different so again, that is a general rule and may or may not apply to a specific PSU.

That said, with an 80 PLUS certified PSU, it really does not matter as long as the demand never exceeds capacity. Why? Because one of the key criteria for 80 PLUS certification is that the PSU must provide a "flat" efficiency curve. A flat efficiency curve is desired for computers because computers are putting a constantly changing and wide variety of loads on the power supply from near 0% load at idle, to near 100% load when taxed. So if you look at "Gold" certified PSUs, for example, they must be at least 87% efficient at 20% load, 90% at 50% load, and 87% at 100% load.

That ±3% difference from the 50% load point really is insignificant.

So while a power supply's efficiency is important for other reasons, it has nothing to do with the "quality" of its output voltages.

Basically your average should be within 40-60% of PSU and ofc peak shouldnt go over what PSU can do.

Well, no and yes. The average demands may be good to know for curiosity sake, but it is the maximum demand possible that MUST be the deciding factor when sizing up a PSU. This is because average demand is based primarily on how the user uses the computer, and less so on the components.

For example, assume two identical computers. If Fred spends 7 hours per day editing Word documents, watching YouTube videos, and reading emails, then 1 hour per day gaming, his "average" power use will be much lower than Wilma who does heaving gaming 7 hours per day and updating Facebook 1 hour.

Now if you are like me, you hate fan noise. When a PSU (any PSU, even Titanium certified PSUs) are wasting a lot of energy, that energy is lost in the form of heat, That heat must be exhausted out of the PSU and computer case. That is done by the PSU's fan. The more heat, the faster - and louder - the fan will spin.

So if you regularly tax your system with heavy demands, you may want a bigger than needed PSU so it will operate more quietly most of the time.

If you rarely push your system to the extremes, the PSU fan may rarely spin loudly and so a smaller PSU may be all you need.

PSU is one thing I never save money on.
I agree completely. Too often I see inexperienced users attempt to trim the budget by going cheap on the power supply. That often is a mistake. I like to ask, "Would you buy a fancy new Porsche then fill it up with generic fuel from the corner Tobacco and Bait shop?" An engine can miss a beat and keep on running. But high-speed digital electronic can't.

***

Side note - a basic, non 80 PLUS certified power supply will typically have a "bell" shaped efficiency curve (as opposed to "flat). That is, they are most efficient (have "peak" efficiency) at just one load level. And another "general rule" is that peak efficiency point for most basic power supplies will be achieved at loads that sit somewhere around 60 - 70%.

And these supplies are perfectly fine for electronic devices that have a fairly constant/consistent power demand. A monitor or TV for example, has a fairly consistent power requirement. Yes, all black will be different than all while, but those are the extreme exceptions and exceptions don't make the rule. So a good design team, when selecting the power supply, will match a supply's peak efficiency with the device's demand.
 
I guess its more of an issue of what the individual may plan on adding to the system later on down the road & if it will require a PSU upgrade ---> If so, now or later? If they do need to upgrade, the former will cost less money in the long run while the latter will cost more since they're essentially buying two PSU for the same system.
 
I guess its more of an issue of what the individual may plan on adding to the system later on down the road & if it will require a PSU upgrade
Sadly, not all plan ahead. So they end up buying a barely adequate PSU today, then have to buy a bigger one down the road. So yeah, maybe they saved a few bucks in the beginning, but it ended up costing them more in the long run.

Of course, it is not always easy to predict what our computer/power needs will be in 2 years, but we should try.
 
I'm running on 750 with 3090 and no issues but I know I'm pushing the limit and plan getting a 850.
 
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Here's a bench form right here on TPU

Graphics Card only Power Draw Peak


The 3090 is a power hog but an 800 watt PSU is more that enough if it is quality.
 
Depends on what PSU that is. If it's a quality one, 800W will be no problem. Especially if you undervolt your GPU (which, you should always undervolt your Ampere cards, I got 100 MHz more on the core clock on my 3070 by doing so and shaved off about 40-50W)

My last unit made by High Power (which seems to be the one here) performed fine but made some awful noises, even the replacement. Was a Fractal Design ION+ 860W. My new Seasonic Prime PX-750 unit doesn't make such noises.
 
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Depending on the specific GPU card model it will require around 350-400W.
Depending on the CPU settings/OC and usage scenarios a 10900KF would require up to 300W. I doubt though it can reach 250-300W on gaming. Around 100-150W is more believable even with the max OC possible. Less without OC.
And then it’s the rest of the system and again depends on the components it would be around 50-150W.

My estimation is
GPU: 360W
CPU: 100W
System: 100W

560W is 70% load on 800W PSU. It’s ok even for a 24/7 usage if the PSU isn’t anything cheap.
Personally, I would be more comfortable with 850W. But thats me.
 
Is the 800W good enough for this?
This would depend greatly on the quality of PSU. Don't cheap out on the component that counts the most to system stability. Also, as was mentioned by another user, W1zzard's own reviews(as well as many others) showed that a 3090 can reach a very high power draw under full load. Given the other parts you're looking at in addition to the 3090, an 800w is going to be cutting it very close. If you can afford to, lean towards a 900w or 1000w PSU to be safe. Better safe than sorry.
 
Couple of things. Get a decent brand PSU in there like Seasonic, Corsair etc. Some Seasonics even have incredible 12 year warranties! High Power are nothing special so don't bother with them.

It's a good idea to "overkill" your PSU's power rating since your whole system will depend on it for years. The PSU will always be operating further away from its limit and hence be running cooler, less stressed out and the fan will come on less often, or maybe even never. Some will say that the PSU will run less efficiently at these lower power levels and it might be true, but just how much difference does it really make to your bills? I'll bet no more than a few dollars a year at the most, which is nothing. On top of that, your power requirements are likely to go up as you upgrade CPU & GPU. Therefore, get that 1000W decent brand PSU and enjoy the peace of mind. :cool:

btw, is that 3090 actually available to buy?
 
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