Opinions on cooler for a Ryzen 3900X?

[Euphonium]

I'm lookin to replace the Wraith Prism cooler that came with my 3900X. Based on the Hexus reviews I'd going to be getting either a Corsair iCue H115i RGB Pro XT or a Noctua NH-D15.

My case is a Fractal Design define 7 with 2x140mm inlet fans on the front and 1x140mm exhaust on the back. I have the option of adding addtional fans top and/or bottom. I'm assuming this will be neccesay because I need to get the heat out of the case, not just out of the CPU

If I go with the AIO what is the best way to mount it? I have space for a 280mm radiator at the front or at the bottom. (I can't mount it at the top as the 5.25" drive bay is in the way)
Which position is better, and do I want the fans drawing outside air through the radiator and into the case, or pushing case air through the radiator and out?

[CAT-THE-FIFTH]

The air cooler should help push some airflow over the VRMs.

[Euphonium]

The air cooler should help push some airflow over the VRMs.

How neccesary is that, especially if I have a fan in the top of the case above the CPU socket, either as a inlet or an exhaust?

[Xlucine]

How neccesary is that, especially if I have a fan in the top of the case above the CPU socket, either as a inlet or an exhaust?

It's nice to have. The case fans will be making sure the air in the case isn't too hot, but heatsinks prefer having air flowing directly over them - it'll literally give you 10x the cooling performance with active cooling rather than relying on the change of density in hot air to supply cool air onto the heatsink. Generally case top fans are positioned off to the side of the motherboard to leave room for radiators, so they don't get that much airflow directed onto the VRM cooler.

If you're trying to set OC world records, you'll definitely benefit from getting an extra fan blowing on the motherboard. In practice for a 3900X, most high end boards are designed expecting to be used with an AIO so they have OTT heatsinks to cope with no direct airflow and will manage just fine

[CAT-THE-FIFTH]

How neccesary is that, especially if I have a fan in the top of the case above the CPU socket, either as a inlet or an exhaust?

The stock coolers are horizontal so blow air over the VRMs. The MSI X570 Gaming Edge and X570-A PRO have quite poor VRM heatsinks so ran quite hot,but not so sure about the Gaming Plus,as they seem more finned.

[Euphonium]

The stock cooler blows it's exhause at the RAM and the VRM heatsink by the IO shield, but not at the VRM heatsink above the CPU. Right now, 5 mins into a handbrake encode, both VRM heatsinks feel about the same by touch, and both are cooler to touch than the CPU heatsink (core temp 89'C) and graphics card backplate (GTX980Ti, 48'C)

MSi Dragon center says:
Chipset - 54'C
MOS - 70'C
CPU - 88'C
Chipset - 54'C
System - 45'C

If I install a top-mounted fan above the CPU socket it would be the same distance from the top VRM heatsink as the rear exhaust fan is from the rear VRM heatsink.

If I go big air I'll put an extra exhaust fan above the CPU socked.

If I go water, I don't know if it will in an intake fan or an exhaust above the socket, it depends on where I mount the radiator (front or bottom) and whether it's drawing air in or blowing out.

[CAT-THE-FIFTH]

The VRM heatsink above the CPU usually covers the SOC VRM,and the one near the I/O shield the CPU VRM. AIO water coolers do look neater and have less socket stress,but a good air cooler should not only cool the VRMs better,but will technically have a longer lifespan. AIO water coolers can last over 5 years,but AFAIK,they tend to be designed to last 4~5 years optimally without maintenance.

BTW,there is also the Noctua NH-D15S which is an offset heatsink version for better compatibility. Having said that a U12S might be OK too:
https://www.funkykit.com/reviews/coo...accessories/4/

That review tests a few aftermarket CPU coolers with the Ryzen 9 3900X.

[Euphonium]

I notice their test figures are done on a 65W 3700X and that they say 3900X users can expect to see temps ~6'C higher, which is so close to what I see with the stock cooler that I don't think the U12S is worth it. If I go air I think it has to be the D15. My RAM is standard height so that shouldn't be too big a deal.

[Phage]

How did you get a 5.25 in the top ? Thers a slot but an ODD sags alarmingly. Looks like it needs a beacket

[Euphonium]

How did you get a 5.25 in the top ? Thers a slot but an ODD sags alarmingly. Looks like it needs a beacket

There's a little bracket in the accessories ack that came with the case

[Phage]

There's a little bracket in the accessories ack that came with the case

Dammit - I didn't get one. I'll ask Fractal

[Euphonium]

Dammit - I didn't get one. I'll ask Fractal

It's a tiny thing, I almost didn't recognise it. It looked liked it wouldn't be strong enough but I screwed it in tightly and it was fine.

[Phage]

It's a tiny thing, I almost didn't recognise it. It looked liked it wouldn't be strong enough but I screwed it in tightly and it was fine.

Can you post a pic ?

[Euphonium]

I can't, sorry. I've got my case in max storage mode so I'd have to half-dismantle it to make the bracket visible.
It's shown (small) on p27 of the manual if that's any help

[MilimNava]

BeQuiet Dark Rock Pro4 is a nice choice aswell.

[Helios451]

Ok, to weigh in.

I have the 3900X on air cooling using a be quiet Dark Pro 4.

I have that in a be quiet case with two input fans at the front and one at the back. I also have internal polythene sheet baffles so that any turbulence in the back to front ventilation is reduced.

The result is a CPU which performs in the 35 to 50 degree range in everything except extreme bench-marking, which really isn't an everyday occurrence, when it can hit 90-ish.

No need for the expense and hassle of an AIO, in my humble opinion!