CPU Cooler Fan Direction on EliteDesk 800 G4

[PupuL]

Related to my question about using a non-HP cooler (https://h30434.www3.hp.com/t5/Desktop-Hardware-and-Upgrade-Questions/EliteDesk-800-G4-TWR-2UZ41AV-CP...) in this chassis: I noticed that the cooler in the computer (the round Intel chunk with radial, curved fins, 863480-001) has the fan mounted to blow air down to the CPU. Is the fan supposed to blow the air down or suck the air up?

[NonSequitur777]

@PupuL,

The CPU heatsink/cooling fan is supposed to blow air down.

With regard to the 95-watt TDP rated CPU heatsink/cooling fan combo with p/n: L30413-001 (L04397-001), this is indeed the best HP-branded heatsink you can get for the HP EliteDesk 800 G3/G4/G5 SFF platforms.

Occasionally you can purchase one of them for $50 or less via eBay.

Another CPU heatsink option you could try is stacking an additional cooling fan on top of the original one, both blowing air down, and using a 4-pin PWM splitter cable, which helps bringing down temps -because, well, you are moving a lot more air to cool things down:

To further increase the airflow through the CPU heatsink, is to cut a hole in the top panel directly above the CPU heatsink, and mounting a cooling fan on the exterior, also blowing air down:

And in addition to that, also mounting a cooling fan on the back of the chassis in line with the CPU cooler blowing air out.

This is one of several cooling options I came up with with my HP EliteDesk 800 G3/G4/G5 SFF upgrade projects: https://h30434.www3.hp.com/t5/Desktop-Hardware-and-Upgrade-Questions/Upgrading-HP-EliteDesk-800-G4-S..., and: https://h30434.www3.hp.com/t5/Desktop-Hardware-and-Upgrade-Questions/Upgrading-HP-EliteDesk-800-G5-S..., and: https://h30434.www3.hp.com/t5/Desktop-Hardware-and-Upgrade-Questions/Upgrading-HP-EliteDesk-800-G5-S....

Hope this was helpful.

Kind Regards,

NonSequitur777

[PupuL]

Dear @NonSequitur777,

Thank you for your kind reply without the corporate yadayada. Your response seems to address also my other question, and I don't know if I should reply to parts of your response that do address the other question in this thread or in the thread in question. Different forums have different established practices, and I don't know what the HP forum practice is.

And just to be extra, super-duper clear, my 800 G4 is the minitower model with a little more space in it than in the SFF model that you refer to.

That having been said, I have a few alternatives now in mind for the cooling and one thing that puzzles me. The alternatives are:

1. using a taller (the heat sink is approximately twice as tall as the HP heat sink) winged heat sink that I salvaged from a junk yard, in which case I need to figure out how to exchange the screws or use a CPU bracket on the backside, and here you could tell me if the existing motherboard already has an exchangeable bracket or not (the thread of the screws on this heat sink is different than the HP standard thread, and the heat sink cannot be mounted on the motherboard without breaking stuff) (no, I haven't taken it out yet; yes, I certainly know how to do it) and if your opinion is that adding more metal to the heat sink, thus adding more dissipation surface, will benefit me
   
2. stacking two fans on top of each other and/or cutting the case to improve airflow and use existing heat sink (the question here is whether that will help with the rather fluctuating temperatures of the i7-8700)
3. using a Noctua NH-C14S, and here the question is how much clearance there is, exactly, in the chassis, seeing as the Noctua is 115 mm tall with the fan in the bottom position and 142 mm tall with the fan in the top position, and my crude measurement puts the clearance somewhere in the 140-mm range but not exactly, and whether using this would still require cutting the cover
4. using the L04397-001, and here the question is whether this should help with the highly fluctuating temperatures of th i7-8700

Finally, your reply has been helpful so far, but I would like to know whether by clicking that it was helpful I am also indicating that it actually solved my questions. Do you know that?

Thank you.

PupuL

[NonSequitur777]

@PupuL,

When you click the "helpful" message option, that doesn't close the thread, it only shows that you indicated that you "liked" a response.  And even if you indicated that any response "solved" your question, we could still engage in comment exchanges, at least for a while when HP "locks" the thread.

Anyway, since you got the MT version, there should be room aplenty to mount any additional cooling fans on the interior of the case, rather than the exterior.

I am somewhat puzzled with the heat you say your i7-8700 produces.

I used an i7-8700K in my smaller SFF case, and heat was kept under control after I implemented the aforementioned cooling fan mods.  Are you using a quality thermal paste such as Arctic MX-4?

The problem with non-HP CPU coolers is that it may require modding your case: since there is not enough space directly beneath your motherboard, Users reported having to cut a section of the sheet metal beneath the processor to allow for the mounting of an aftermarket CPU bracket.

Again, I would go for stacking a CPU cooling fan, and for adding a cooling fan directly above your CPU heatsink, just like I did with my SFF case.  Remember, the idea is to improve the overall air flow, especially through your CPU heatsink.

Kind Regards,

NonSequitur777

[PupuL]

Yes, MX-4 specifically. Albeit the syringe has been opened a couple years ago. The sealed syringe is MX-6. Will try with that once the 95W cooler arrives.

In the meantime, any advice on the thread of the winged heat sink?

[NonSequitur777]

@PupuL,

The Noctua NH-C14S according to customer's reviews appears to be an OK CPU cooling option, but it is not something I personally would go for:

Let me show you the most recent CPU air coolers I purchased for various PC upgrade projects (mostly non-HP related) via Amazon alone:

There is not necessarily a "wrong" CPU air cooler, mostly it is based on a personal preference.

Kind Regards,

NonSequitur777

[PupuL]

A little bit of troubleshooting shows that disabling Turbo Boost on the i7-8700 completely eliminates the fluctuation and fan ramp-up. Adding a second fan on top of the first one to blow more air in did not eliminate the fluctuation or ramp-up. Whenever the CPU goes on turbo mode, the heat sink is insufficient. So, I am running it now without Turbo Boost until I get the 95W heat sink.

I am wondering, though: do you have information about the thread used in the HP cooler? Not compatible with the more massive cooler I have, and, after removing the motherboard, I can see that the mounting holes for the CPU cooler are on the chassis itself, which means that I am stuck with whatever thread is used. It would be truly helpful to identify the thread.

[NonSequitur777]

@PupuL,

There are ways to mod your PC in order for non-HP CPU heatsinks to be installed.

I invite you to take a look at this YouTube video:

Link: https://www.youtube.com/watch?v=UfIL7x1reDM.

Kind Regards,

NonSequitur777

[arch1985]

Yes, it is possible. I was able to get Thermaright Peerless Assasin 90 SE installed in Hp Elitedesk G4 800 Tower for i7 8700 processor. The fan connector is perfect. Refer to attached picture. The cooler is amazing and cost less than €30,00 in Germany.

Important tip, Use the supplied AMD Spacers and AMD screws since they go on HP Chasis directly. The plate to install foot of heatsink is Intel but the screw holes a bit small. Use a screw driver to make the holes a tad bigger so that AMD screws goes through. There is a YouTube video also done by someone check it out. It is named as 

HP Elitedesk Tower Max Out CPU....

Good luck.