semi fanless operation mode information request, experts click here

[Laststop311]

I will get right to it. I would like to know if getting a higher wattage power supply also gets you more watts till the fan kicks on. Corsair says the zero rpm fan mode works from a 0-30% load. So the conclusion I've come to is a 1200 watt psu would give you 360 watts before fan kicks in but a 600 watt psu only gives you 180 watts before fan kicks in. Is this basically how it works?

I need to know because under maximum full stress mode my system uses 450 watts but more typically around 300 watts. So when I get the new psu if I get the 1200 watt psu, even though i dont need 1200 watts it will keep the psu in fanless mode most of the time and still have a fan for backup incase it gets too hot, it should give me 360 watts of fanless.

Will the 1200 watt one stay in fanless mode more than the 750 watt one talking about the corsair HXi series?

 

[ignatzatsonic]

I wouldn't trust Corsair data sheets on that issue, regardless.

Instead, I'd hope to hear from owners who can report their personal experience with that particular power supply.

I've seen similar confusion and questions regarding the same situation on Seasonic and EVGA semi-fanless power supplies. Some say the fan actuates by load only. Some say it actuates by temp only. Some says it's some undetermined combination. Customer service reps may tell you something that doesn't match what is said in the data sheets, leading to more confusion. It's fuzzy.

The PSU engineering staffs of the manufacturers might have an accurate answer, but you don't have much chance of hearing from one of them directly. You get the marketing stuff.

So, hope you can find several owners and get their personal results from their personal tests, properly conducted.

 

[Cerb]

I will get right to it. I would like to know if getting a higher wattage power supply also gets you more watts till the fan kicks on. Corsair says the zero rpm fan mode works from a 0-30% load. So the conclusion I've come to is a 1200 watt psu would give you 360 watts before fan kicks in but a 600 watt psu only gives you 180 watts before fan kicks in. Is this basically how it works?

If that's how it works, yes. Some will do it by temp, though, instead.

IMO, if you want it to remain fanless all the time, though, you should just get a fanless PSU. Seasonic and Super Flower make good ones, sold under quite a few different brands. Make sure there's some case air flow exhausting through the PSU, and it'll be fine. It's more expensive, yes, but then you're done. No need to worry about it for the life of the PC, and maybe the next one, too. Since they're all 80+ Gold or better (most are at least Platinum, now), the total heat they'll be making will not be much.

 

[fleshconsumed]

If your system uses 450W under torture tests, why not just get a completely fanless PSU?

http://www.newegg.com/Product/Product.aspx?Item=N82E16817182169

This PSU should do it, it's currently OOS, but it seems to come back in stock every so often.

 

[Cerb]

I'm using that very one. The Kingwin passive 500W and Silverstone passive 500W are the same PSU, as well. It's a Super Flower Golden Silent, if memory serves.

 

[DaveSimmons]

Have you tried a Seasonic Gold PSU? For the two I've owned (5xx watt, 6xx watt) the fan is extremely quiet under non-gaming loads. Even if I had my desktop sitting on my desktop I'm not sure I'd be able to hear it from a foot away.

Fanless will be silent, but then your case fans will need to work harder to move the PSU's heat out of the case.

 

[fleshconsumed]

True, most quality fanned PSUs these days will be practically silent. However, the reason I like fanless PSUs is because every fan has a finite lifespan. Every single fanned PSU I have owned have developed some chirping/grinding/clicking noise after few years of life and while you can easily replace a system fan, you can't replace PSU fan without voiding the warranty. And even then, you still need to find exact fan to match what's in there and you will also probably have to solder proper connector. Too much nuisance and effort for me, I'd rather go with fanless.

 

[ignatzatsonic]

If your system uses 450W under torture tests, why not just get a completely fanless PSU?

http://www.newegg.com/Product/Product.aspx?Item=N82E16817182169

This PSU should do it, it's currently OOS, but it seems to come back in stock every so often.

I've been using one of these successfully for the last few months. No coil whine; no issues. It's not fully modular, but the cables are quite flexible and can be stashed easily.

I'm not sure it will be back in stock at Newegg. I tracked the price at Newegg for 6 months or so and it ranged from 120 to 160, sometimes with rebate, sometimes not---until a couple of months ago when it was available at 90, no rebate. That may have been a clearance price? The model is a few years old, so maybe a replacement is due.

Superflower has a 430 watt fanless model, but it's unseen in the USA and I don't think it has ever shown up with the Rosewill badge. I'd have bought the 430 if I could have as my system can't use even 200 watts.

 

[freeskier93]

Is PSU fan noise really an issue these days? I have an EVGA with the eco mode that turns the fan off at low load, but I don't turn it on. It's completely inaudible at idle and at load there's no way I can discern the PSU fan from the other fans. The only way I can imagine you'd notice PSU fan is if you have a completely passive system, but we are a long way from that for performance computers.

 

[Bearmann]

If you decide not to get a fanless PSU, note that if JonnyGuru has reviewed the semi-fanless PSU, he notes at what percent of the specified power that the fan kicks in. Other sites may also provide this information.