First, thank you to bdr33733 for sharing his inspiring project.
Second, allow me to add my own specific experience to bdr33733's. This is meant as complementary to bdr33733's guide, not a replacement.Modding the HP dv6-06b88ss
RESULTS & CONCLUSIONS
1. Replacing the thermal paste was a must.
The old thermal paste was dried and not covering the whole thermal surface of the CPU.
2. Making a fan inlet makes a significant improvement on both temperature and fan noise.
This CPU stress test graph shows the temperature with the fan inlet hole unblocked (A & C) and blocked (B). What the graph does not tell you is that, first, the fan was not running at maximum, but kicked in max after about 30s of blocked inlet (B), and second, the sound pitch of the fan is lower with the inlet as it's not working as hard (I hear more air flow and less motor… less annoying to my ears)
I decided to go with bdr33733's 2nd approach: round inlet. And size it as close to the fan inlet size, which is 40mm (a little less than 1 in 5/8). Also, I disassembled the back speakers and the display assembly to make is easier to work with the base cover and less risky to damage the LCD. I do not have a dremel, but I have a drill and got a circular saw. Here I go…
a. Used a sharp needle to mark the bottom and have a location reference
(after note: I could have simply removed the fan from the heatsink, put back the motherboard in place, and mark the fan circle with a pen or marker... it would have been a lot simpler... and more accurate.)
b. Marked the center.
Notice the 2 grills (50mm and 80mm), I choose the 50mm because the third ring from the center is the closest to 40mm, on the 80mm it was about 48mm. Also, the 50mm grill use thinner wire.
c. Drilled the center.
d. Drilled the hole with a 41mm circular saw. (cut slowly and in steps, so the plastic does not get hot and melt)
e. The hole.
Notice the uncut inside metal plate? Pay attention. My initial idea was to cut the inside plate with a slightly bigger circular saw, so I would get room to sit one branch of the grill. Well I screwed up. While trying to cut the metal plate, it got hot enough that it started to melt the plastic. But I did manage to cut enough so I could break the plate by plying it and fiddling with it… eventually and then filed the edge of the metal plate.
f. Fixing the grill. I used metal epoxy.
g. Prepare for more epoxy. I need to add epoxy all around but the outer ring is 40mm and the hole is about 41.5mm, that means that the epoxy might very much overflow underneath. So... I made a strip of very thick paper (like business card) and folded box tape so the edge would not stick too much to the epoxy and then placed it in the gap.
h. Positioned the paper strip while I had the bottom elevated.
i. Applied the epoxy all around.
j. Before the epoxy get too hard I removed the paper strip.
k. Cut top exceeding epoxy off the branches. I'm putting a metal mesh (to catch anything bigger than dust) on top of the grill (from inside) and I need to keep the final result as thin and low as possible, so it does not touch the fan.
l. Press it while hardens. As soon as the epoxy is applied around the mesh I covered with a food wrapping cellophane, card board of appropriate size and some weight to flatten as much as possible, the mesh and the epoxy.
m. Flat mesh.
n. Outside result.
1. Mesh on the fan case. My first approach did not work because the center of the fan exceeds and touches the mesh.
2. Cutting the inner metal plate with a circular saw. As I mentioned, cutting the metal plate was getting it hot enough to melt the plastic underneath. Lucky me I stopped remembering that metal cutting can become quite hot.
(post note: I'm still wondering what would be the easiest way to cut that metal bracket. The circular saw could be done, but with a press drill to stay dead center, and by step to keep temp below plastic melting. Another alternative is to remove entirely the metal bracket, cut out what's in the way, then put it back and glued... but that is a little more complicated because one of the screws holding it is unreachable. Otherwise the dremel is probably the easiest approach.)
Here is what it looked like before I put back the heatsink back. The MX-4 seems to work well (time will tell). As shown earlier, original paste was a waste (after 5 years of use) and from close examination it did not seem like it was covering the entire thermal surface.
Fan is not clipped. On all the jammed fans I have opened, there were little clip to keep the blades in place. To my surprise, while vacuuming the fan the blades came off and discovered that it's only holding by magnetism. So I took advantage of that to put new oil on the center axis.
That's it folks.