Hi everyone, I am trying to decide the best way to install a low profile CPU air cooler based on the components it will be blowing air onto.
Generally speaking, there seems to be a choice about:
How much the heatsink/fan overhangs (and thus blows hot air onto) the memory versus the VRMs
Proximity of the exposed heatpipes to the VRMs, memory, or M.2 slot populated with a PCIe drive
Different coolers have different amounts of overhang and proximity, but what should I aim for? The memory have heatspreaders, just as there are two good size heatsinks on the motherboard for the VRMs (is that were the chipset is too?).
Agree, case cooling is always important. But conceptually, with a low profile cooler that overhangs some mobo components, I am curious if it’s better to avoid VRM vs. memory (and M.2 isn’t too far away either).
Having the cooler overhang the memory or the VRM may not add cooling – it might be blowing hot air from the CPU onto those components and heating them up.
For sure, but the exit air is warmer than ambient and maybe(?) warmer than a VRM or memory? You seem to think it will not be?
If I was sure the air won’t be heating anything up, exiting over the VRM is best I take it. If it was, the implication is heating up the memory a little is better than adding to the VRM?
If anything, have the copper bends facing downwards [avoiding to contact any existing VRM HS].
With LP CPU Heatsinks, you’d likely need to worry over [existing/planned] RAM sticks. Larger spec’d build [ones that use 120mm fan], would have the fins height to pcb relatively short. In turn, not allowing taller RAM sticks [RGB / overbuilt-HS] to be used
Can you explain this in another way? As I see most low profile coolers, the heatpipes come out of the base, bend away and more or less 90 degrees up from the mobo, then bend another 90 degrees (back parallel to the mobo again) as they enter the heatspreader. You don’t have much choice about that, but depending on the cooler, you have usually 2 to 4 directions they can be facing, also depending on clearance.
Speaking of clearance, yes, RAM clearance is a factor, but I wanted to keep this question focused just on the potential heat effects. @mutation666 seemed to think that the heatpipes won’t radiate all that much heat, though I can’t imagine those hot pipes won’t be putting out anything.
I would suspect, with no experience, that the VRMs will be hotter than the air off the CPU. They should at minimum be not affected or maybe even benefit form the extra airflow.
The air has to go somewhere and of all your choices that is the best one as everything else definitely does not want any extra heat and likely to be more sensitive to a change in temperature.
The heat pips will give off heat but they are not set up to give off heat by themselves so would not heat up the air around them to any significant degree, any airflow in the case at all would counteract their added heat. The real heat is given off by the fins and the added surface area they give.
Keep in mind that the temperature reported by the CPU will be lower at each step away from it because heat will not transfer at 100% efficiency,
CPU >
Solder/Tim >
Integrated Heat Spreader >
Thermal Paste >
Cooler Base Plate >
Heat Pipes >
Coolers Fins >
Air
Each step slightly lower temperature than what is reported by the CPU. After all sitting in a room with a CPU cooler blowing out 70°C air would be unbareable for anyone, the air is not that hot at all.
I’ve used several low profile coolers and almost always something else in the build will limit how it can be installed. In an ITX build you have a RAM and a GPU to deal with for sure, but on some motherboards even the VRM could get in the way. In a situation like any of those then pick a direction that doesn’t touch anything else, and if you have more than one option, pick whatever makes it the easiest to work around.
As for thermals, that very much depends. Memory chips can actually handle a lot of heat, but the controllers less so. Even at that as long as the controller is below like 85C it’s fine. The VRM depends on the specific components, but generally VRM can handle being quite a bit hotter. Like some VRM are rated at 125C. For both the RAM and VRM the CPU cooler may actually help cool them because of the very direct air flow wicking away the heat.
Regardless, in my experience, with a non-overclocked CPU we’re talking about maybe a 5C increase at most on any component directly underneath the cooler compared to if it wasn’t. And that would be in an instance where there is basically an air dead zone against the component. That can be solved by better case fans and/or case fan layout.