Corsair RM850 2019 fan replacement

[AnonymousGuy]

13 hours ago, Dogzilla07 said:

There's one fast, easy option for <1000W PSUs that already had a gentle fan curve, and that's running the fan off the motherboard at a fixed value (ideally). Running a curve out of GPU temps can work if the CPU doesn't use many watts (12400/F, 12500/F, 12600/F, 5600/x). 

Corsair at least IME has a safety where if it doesn't see the fan spinning when commanded it'll click off like OCP tripping.  I shoved some wire in the fan once to stop it for full-silence and it didn't like that.

[Guest]

14 hours ago, Dogzilla07 said:

I'd still go with the Noctua, though, and run it fixed on at least 1200RPM, or more if the noise permits it (as fast as you're comfortable for daily use).

Have you done this before?

[Dogzilla07]

2 hours ago, jonnyGURU said:

Have you done this before?

Yeah, many times, have a Seasonic M12II-EVO 750W running on Cooler Master Silencio FP for years now (~160W CPU + ~170W GPU though). But It did also run for a few months as a test (at about ~700W). Also run a Seasonic X-760W Gold for a bit before I gave up gifted it due to extreme coil whine. Did it for a friends Super Flower. And gave the advice to a couple of peeps on overclock . net forum over the years (some with modern platforms), they had no complaints.

 

There's a few pieces of practical advice to minize any problems, but most of the time it'll just work good enough.

 

1. Putting a bit extra insulating tape over the wire where it gets pinched by the metal sides of the PSU, just for additional safety.

2. Don't drill big holes, keep the faraday cage effect as intact as possible.

2. Keeping the plastic air guide in good shape

2. Double-check Cybenetics/a review of the fan behaviour, to get an idea of how low the fan can be spun (If the PSU has bigger heatsinks/more efficient design and a fan that doesn't brake too much RPM, you can easily run a fixed fan speed that's close to the stock fan speed at near max load, and for some PSUs that can be as low as 800RPM.

3. But in general a great fan at 1000-1400RM is the way to go

5. Not double-ball bearing, but one that will work in horizontal orientation for a long time (this took me quite a while to figure out, the rabbit hole for bearings/motors is deep xD). Your post a while back about matsushita/rifled bearing on both sides + grill shapes reminded of the adventure of understanding bearings.

4. LCP fans are a game-changer for this tinkering, and A12x25 is the strongest performer for the noise < 1200RPM beating even Phanteks T30-120 (the Phanteks gets better >1200RPM).

5. But realistically a fixed 1400-1500RPM speed with the A12x25 is as much noise as a 1200RPM for non-LCP fans, and there's no motor noise, no resonance, no vibration, so it's easy to get used to.

6. And a 1400-1500RPM A12x25 will cool 99.9% PSUs (of any wattage/power usage combination) as good or better as their stock fans xD

2 hours ago, AnonymousGuy said:

Corsair at least IME has a safety where if it doesn't see the fan spinning when commanded it'll click off like OCP tripping.  I shoved some wire in the fan once to stop it for full-silence and it didn't like that.

That's a shame(and I approve of the measure), but easily fixable, if memory serves me correct one guy solved it by running a secondary fan's cable into the PSU, connected to the PSU and running it inside his case, outside of the PSU itself. (He did spend some time matching a fan to not trigger OCP, but his effort paid off). He of course had the wire of the fan cooling the PSU itself come inverse and connected to the mobo (no PWM, no ramp-up, just DC-controlled fixed speed forever).

 

I vaguely remember reading a multi-month journey where someone also jerry-rigged a way to trick the corsair PSUs without using a fan, I don't remember the details, though.

 

I do the same with GPUs. I make great effort to get Zotac, or other models for which the shroud and stock fans are made to be removed/or so easily removed without removing the heatsink, I carefully remove it as soon as I buy a card, zip-tie 2-3x 92mm fans, or 1-2x 120mm fans and set them to a fixed speed on the mobo (not following any component temperature). No fan in my systems has been following no component temperature for almost 10 years now.

 

When I wanna sell, or if I need to return it, or gift, I carefully put the stock fans back (and nobody can tell the stock fans and shroud were ever removed ). A benefit of this is the stock fans being unused, is the best gift the person who buys my used card will ever experience without knowing xD. That and well I sell cards with a few months left in the warranty, so I don't have to deal with a buyer/or a card even if it breaks after I sell it. And because I never used the stock fans for more than few days, I know they're factory new.

[Guest]

35 minutes ago, Dogzilla07 said:

Yeah, many times, have a Seasonic M12II-EVO 750W running on Cooler Master Silencio FP for years now (~160W CPU + ~170W GPU though). But It did also run for a few months as a test (at about ~700W). Also run a Seasonic X-760W Gold for a bit before I gave up gifted it due to extreme coil whine. Did it for a friends Super Flower. And gave the advice to a couple of peeps on overclock . net forum over the years (some with modern platforms), they had no complaints.

They must not be running anywhere near the PSU's maximum capability and running the PSU intaking 25°C ambient air.  At higher temperature, near full load, during my thermal tests, I can't keep components within spec if I'm only spinning 1200 RPM. 

 

I mean.. people tend to over simplify these things.  If throwing a Noctua in a PSU and running it at 1200W is the ultimate solution, why doesn't every PSU manufacturer do that already?   Blade shape is easy to copy, so there's no monopoly there.  It's because a 1000W PSU needs to actually put out 1000W and last for 10 years.  Not 750W and then shut down due to OTP or explode in 5 years.  Then it's not really a 1000W PSU, is it?  That's what makes fanless PSUs what they are.  They're not lower wattage PSUs with better passive thermal dissipation.  They're the same PSUs you would buy with a fan in them, but with the fan taken out and derated to only operate at a lower output wattage.

[Dogzilla07]

On 8/19/2022 at 1:21 AM, jonnyGURU said:

running the PSU intaking 25°C ambient air.

I don't use air con, they did a couple of summers with 35C for weeks xD.

On 8/19/2022 at 1:21 AM, jonnyGURU said:

They must not be running anywhere near the PSU's maximum capability

Almost maxed out, the dinky Seasonic GM2/M12 EVO bronze double forward, group regulated antique 

On 8/19/2022 at 1:21 AM, jonnyGURU said:

At higher temperature, near full load, during my thermal tests, I can't keep components within spec if I'm only spinning 1200 RPM. 

Absolutely, needs to spin more depending on the situation, it's case by case basis (user needs to adjust it to his unique situation, and most users wouldn't know how, for how many RPM, bother to test it out to find the lowest viable speed. So it would turn into an RMA  nightmare if it was set like that from the factory ), but the Noctua has 2000RPM range same as usual PSU fans, it's a hybrid design, great static pressure.

On 8/19/2022 at 1:21 AM, jonnyGURU said:

If throwing a Noctua in a PSU and running it at 1200W is the ultimate solution, why doesn't every PSU manufacturer do that already?

Horrific RMA rates (because it's on the user to adjust the fan speed as required for the PSU to not OTP for every component change, OC, etc, ...), Cause the fan is new, the technology is very new, it's expensive, more like something for halo units up until now +it won't do 10 years on higher temps on high wattage PSUs consistently enough to pass testing. 5 years give or take a year, sure, anything more than that and the Noctua almost certainly starts failing way more often.

 

Given enough time though (realistically at least a decade), most fans in PSUs will be LCP-made, just the cost-effectiveness and ease of manufacturing needs catch up.

On 8/19/2022 at 1:21 AM, jonnyGURU said:

It's because a 1000W PSU needs to actually put out 1000W and last for 10 years.  Not 750W and then shut down due to OTP or explode in 5 years.  Then it's not really a 1000W PSU, is it? 

The passive comparison isn't really applicable, the Noctua A12x25 would already be displacing more heat than stock fans at similar temp/speed. For example even for extreme wattage units fan in AX1600i doesn't go over 2000 RPM and is 1400RPM at 1400W. The A12x25 would do similar. Super Flower Leadex 2000w Platinum fan also doesn't do over 2000RPM, Silverstone Hela 2050, Be quiet Pure Power 11FM and so on. The Noctua a12x25 can match any of those 140mm fans, match/beat any 120mm fans for similar or slightly less noise. 

So, yeah for the very 0.1% of the high watt PSUs it's gonna end up spinning closer to max speed of 2000RPM. But for most anything 650-850W, the A12x25 is gonna produce way less noise while keeping the PSU running smoothly. the LCP is just that much of a game-changer noise/RPM wise

[Dogzilla07]

I apologize if I gave the wrong impression, fixed fan RPM is not something that's ever gonna be viable for a company to do on on anything but <~500w Halo/Premium PSUs. It's just something that's too personalized (+ requires decent tinkering/stability testing/researching of actual Power usage of currently used components)

[The_Hackintosh]

Hi guys, here i come with an update and it was an massive SUCCESS! Required some drilling but else man... Worked out perfectly/like i imagined

Fan runs at fixed 1000RPM/7V and is EXTREMLY silent. Just wanted to update that neither me or my dad got injured and we had a lot of fund doing it and if even i (14) can dismantle the PSU and drill the holes in the fan you can too! My dad just made the cutout in the psu to route the 4pin to the MB because of sparks. Here i have some nice pics i took and the proof of doing so.

 

 

This was an hell of an ride but was worth it, was WAY easier than watercooling/ Krakening G12'ing a GPU. If you made a custom loop before then opening and modding a PSU is a breeze

 

Thx to @jonnyGURU@Dogzilla07@LIGISTX@AnonymousGuy for your help!

 

[Guest]

1 hour ago, The_Hackintosh said:

Hi guys, here i come with an update and it was an massive SUCCESS! Required some drilling but else man... Worked out perfectly/like i imagined

Fan runs at fixed 1000RPM/7V and is EXTREMLY silent. Just wanted to update that neither me or my dad got injured and we had a lot of fund doing it and if even i (14) can dismantle the PSU and drill the holes in the fan you can too! My dad just made the cutout in the psu to route the 4pin to the MB because of sparks. Here i have some nice pics i took and the proof of doing so.

 

 

This was an hell of an ride but was worth it, was WAY easier than watercooling/ Krakening G12'ing a GPU. If you made a custom loop before then opening and modding a PSU is a breeze

 

I wouldn't say it's a massive success until you run your PC at full load on a hotter day.

 

I still can't help but feel a little perturbed that people think that cooling a PSU across a wide range of loads is as simple as fixed 1000 RPM with Noctua's fan blade design.  If that was proper thermal engineering, everyone would be doing it.

 

[Dogzilla07]

11 hours ago, jonnyGURU said:

Noctua's fan blade design. 

1. True for every Noctua fan except the LCP-material made A12x25

11 hours ago, jonnyGURU said:

fixed 1000 RPM

Y, completely agree. OP/his dad will have to adjust that fan speed manually as soon as ambient temp+load changes (if they did calculate the necessary speed for the given setup (i haven't seen parts mentioned).

 

And while a good fan that 140mm noctua used by OP+his dad is not the best/best option. The future LCP-material made A14x25 will be (or a good contender from a different company), in ~mid-to-late 2023 hopefully.

 

11 hours ago, jonnyGURU said:

Noctua's fan blade design

This is not immutable, Be Quiet! completely changed the inlet scoop for their Dark Power Pro 12, to fit their Silent Wings 3 fan blade design (and they even managed to go away with the plastic airflow guide). So, no, adjusting the fan blade design to the PSU specifics is not the only option (It's just the most sensible, most fiscally responsible xD). You can always just do the exact opposite (adjust the whole PSU design to specific fan blades instead) and achieve the same/similar effect. But then you need years of expensive Halo product sales to recoup the R&D, and years and years before it trickles down to high volume products.

 

And don't get me wrong LCP enables brute-forcing, but for the future for serial production LCP-fan use, a LCP-fan with blade design for PSUs, or a redesign of the PSU itself to fix those future fans will be necessary. (I'm very interested to see how MSI's Silent Gale P12 fairs in their new Ai P PSU line, and if they did any design changes to the PSU itself like Be Quiet did.