[SOLVED] How important are VRM heatsinks?

[1405]

I have heard (one of the regular posters here) that the heatsinks on the power transistors for the VRM can actually retard cooling by blocking air flow to the chips. Especially the ones that have that huge shroud in conjunction with the heatsink that extends to the IO port area: Example
Now I'm wondering if what I thought I knew was all wrong. Is it better to buy a board for overclocking the CPU that has no heat sink on the MOSFets? And let the chip breathe?

 

[drea.drechsler]

I have heard (one of the regular posters here) that the heatsinks on the power transistors for the VRM can actually retard cooling by blocking air flow to the chips. Especially the ones that have that huge shroud in conjunction with the heatsink that extends to the IO port area: Example
Now I'm wondering if what I thought I knew was all wrong. Is it better to buy a board for overclocking the CPU that has no heat sink on the MOSFets? And let the chip breathe?

I believe the poster may be referring to the shroud in particular, not the heatsink. A heatsink shouldn't have any plastic on it or it defeats the purpose of the heatsink....which is to expose as large a surface area as possible to airflow in order to shed the heat it picks up from the FET's.

Maybe if you at least quoted the post that you refer to it would be easier to correct any misunderstanding.

 

[1405]

Thanks for the reply. Btw, I just realized I used an un-overclockable motherboard as an example above. Corrected
I'll have to see if I can find the post. It was a post by someone else that I just happened to read. But your statement makes sense. So, the heatsink is still preferred then?

 

[NightHawkRMX]

Yes having vrm heatsyncs is almost always a good thing. Even some poorly designed heatsyncs will still have sone cooling effect. A lot of it comes down to how much air flows over vrm and heatsyncs. Downdraft coolers, stock non tower kind will blow air over the vrms but tower coolers may not. I have also heard the shrouds do sometimes cause excessive vrm heat.

 

[1405]

Yes having vrm heatsyncs is almost always a good thing. Even some poorly designed heatsyncs will still have sone cooling effect. A lot of it comes down to how much air flows over vrm and heatsyncs. Downdraft coolers, stock non tower kind will blow air over the vrms but tower coolers may not. I have also heard the shrouds do sometimes cause excessive vrm heat.

OK, looks like heat sinks are still needed.
I was thinking of using a Hyper 212 RGB Black Edition cooler on an i5-9400f. Since the Hyper 212 blows across the VRMs, wouldn't that add to the cooling?

 

[NightHawkRMX]

If your not overclocking you can go without vrm heatsyncs, but for high end cpus or overclocking motherboards, they are a very good to have feature. Hyper 212 fans are higher above the vrms but they may help a little. For a locked midrange cpu you should be fine without a ton of cooling.

 

[DSzymborski]

OK, looks like heat sinks are still needed.
I was thinking of using a Hyper 212 RGB Black Edition cooler on an i5-9400f. Since the Hyper 212 blows across the VRMs, wouldn't that add to the cooling?

I'm not following; the Hyper 212 is not a downdraft cooler. It's a tower cooler meaning that the main direction of the air flow is across the fins of the CPU heatsink.

 

[1405]

I'm not following; the Hyper 212 is not a downdraft cooler. It's a tower cooler meaning that the main direction of the air flow is across the fins of the CPU heatsink.

What I meant was, the cooler would blow above/over the top of the VRM heatsink. I'm thinking that would take away the heat rising from the VRM heatsink. No?

 

[1405]

If your not overclocking you can go without vrm heatsyncs, but for high end cpus or overclocking motherboards, they are a very good to have feature. Hyper 212 fans are higher above the vrms but they may help a little. For a locked midrange cpu you should be fine without a ton of cooling.

But the i5-9400f isn't locked, is it?

 

[DSzymborski]

What I meant was, the cooler would blow above/over the top of the VRM heatsink. I'm thinking that would take away the heat rising from the VRM heatsink. No?

Only a tiny bit, really. It's a pull and it's not directly in the path. It's a bit like putting a plate of hot food behind a fan.

 

[NightHawkRMX]

9400f is non-overclockable. I wouldnt care much about vrms for that cpu.

 

[1405]

Whoa! Now I am confused. CPU World lists the i5-9400f as having an unlocked multiplier. I'm glad you guys are here. I almost bought it to OC. Looks like I'm going to have to spend more!

Notes on Intel Core i5-9400F

The processor has unlocked clock multiplier