38*c Drop in Temp after Heatsink MOD!

After upgrading my processor to the t9900 on a p7811fx laptop my temps were higher than I was comfortable with. I needed a cooling fan just to have it on.

Temps with bottom cover on and no cooling fans were as follows:
at idle:tzs = 71c and after 1/2 hour of cod = 91c
at idle: CPU = 63c and after 1/2 hour of cod =86c

I put new ic diamond 7 and copper shimmed the chipset and only gained a few degrees. Cooling pads only dropped it to 50's and 60,s with maxs in the 80's and only workes when at home.

There are other heatsinks to upgrade to so I looked to improve on what I had.

After ordering 2 extra heat sinks $10 each (ebay) and playing around with different ways to modify them I finally came up with a mod that blew my socks off!

Cover on, no cooling fans:
At idle, tzs's = 33*c and 1 hr cod only hit 59c max
At idle, CPU = 25*c and 1 hr cod only hit 53c max

It now idles 38c less! and max temps are 33c less!

I won't bor you with the ones that didn't work as well but the best results came form using a copper heatsink from a after market VGA cooler. (Vantec Iceberq 6 from Newegg $29.99)

#1 I had to cut off the copper block from the bottom and file/buff smooth. (That was a pain but the rest went smooth)
#2 I cut it the shape of the stock heatsink / heatpipe.(Hack saw)
#3 Filed the top of the existing heatsink and buffed smooth.
#4 Used icd7 on heatpipe and Arc silv 2 part epoxy on aluminum block.
#5 I clamped the new "cut to fit" heatsink to the top of the stock one.
#6 Cut a hole in the bottom cover to fit around the new heatsink. (Fein tool)
#7 Added new 1/2" rubber legs to hold the laptop high enought to clear the new heatsink.

Here are pictures of the process and the end result. (They are numbered 1-10)

HTML:

http://photobucket.com/cacheflowuploads

(I have a back up heatsink and cover if I ever need to return to stock.)
I am also going to design a vented cover to protect the exposed heatsink.

 

Oops, Here is the link:
Pictures by CacheFlow123 - Photobucket

 

I used to have a 7805 and I must say that is an awesome mod you have done. Thumbs up to you for innovation. Now-to find somewhere to stick/fit that HS in the case.

PS:Nice lappy feet!

 

It can be done! The whole thing can be made out of copper, make it a little thicker and incorperate cooling fins into and around the heatpipe all confined into the avalible space. The current heatsink is rated for the 8400 processor and works efficiently for that processor. Because of cost the only do what is necessary. If I had the right tools or enough money I could fab one that fits no prob.

 

This is fine so long as you never intend to take the laptop anywhere or move it ever again.

What you've done is compromised the ESD shielding the case itself provides. Laptops can be made of plastic, but there's always a metal shielding beneath to make up for it, even if it's essentially tin foil. The 78xx/79xx series cases are thankfully metal. You also rested the laptop on a *cotton towel* after doing so, which was risky in and of itself without the ESD shield being compromised.

Neat mod, and I'm glad it's made such a difference, but just make certain nothing statically charged ever makes contact with that highly capacitive copper. To be extra safe I'd get a rubber welcome mat or something to rest those "laptop booties" on.

 

Thanks for the input. I used a wristband to ground myself and thought that is would be enough. Didn't think about the cotton towel. My bad.

As far as the metal shielding goes the rest is still in tact but you are right, the new heatsink is now exposed and un protected against static charge. I am fabing a vented cover for protection against bumping. Do you have any sugestions on how I can design the cover to also prtect against static?

Why would I not be able to take it anywhere or move it again?

 

Well, you've gone this far, so why not fabricate a plastic/or non metallic cage(perforated with holes) around heat sink.

 

A plastic cage is exactly what I was planning on. It was the EDS shielding that DestruyaX mentioned which was "compromised" that I was worried about and why he thought that I could "never take the laptop anywhere or move it ever again". It is fully portable.

 

I think he was just suggesting that if you do not protect it better, that he personally would not risk moving it. I think if you design a nice cover for it, it will be fine. As far as where to find one or how to go about fabricating one-

 

Thinking fish filter cover or strainer basked or something to start with. I don't know yet but I'm pretty MacGyverish.

 

OR you could wait and get this:

Thin heat sink

 

Wow, looks like it is based on actual cooling the processor vs. transfering heat away heat and disapation.

2 problems $750.00 starting for the 2000rpm and still too big for my laptop.(85mm x 55mm or 3 1/3 " x 2 1/4" little less)

But again, wow! That will help laptops and notebooks in the future!

 

i used to have a similar problem when i installed a X9100 into my 7805u.

For a couple of months, i was totally confounded by the fact that my X9100 idled at 50-60C whilst other forum members reported idling @ 30C.

i then resorted to a couple of cooling mods, evidenced here (post #30):
http://forum.notebookreview.com/gateway-emachines/505982-x9100-results-7815u-3.html#post6566804

temps improved but still nowhere near 30C. Eventually found out that when i originally installed the X9100, i overtightened screw 5 (the one with the spring) that clamps down over the NB chipset. In doing so, i FUBARed the spring which had the consequence of the heatsink maintaining "bad" surface contact with the chipset (due to lack of tension).

i ordered a new heatsink and backpanel off ebay. I immediately noticed a difference when tightening screw 5 on the replacement heatsink. Can happily report that i idle @ 31-33C @ 3.2GHz with only ICD7 application; not even a copper shim applied. Under load @ 3.6GHz, i only hit 68C.

Wouldnt be surprised if the same thing happened to you too. In short, the stock heatsink is more than capable of handling a X9100 or t9900.

 

When you say under load are we talking an extended run of Prime95 or normal high loads?

I have been thinking of a similar mod but not as extreme. I just ordered it, This HS and I will remove the fan and screws. This should alow me to cut the back pannel over the CPU so that with this over the cpu portion of the HS it should then be flush with the original surface.

Edit, a simple mod is to remove the RF shielding off that back pannel. It won't help idle but it does increase the air flow out the CPU vent.

 

I tried a similar sized heatsink made of aluminum (one on each side of heatsink) and it did drop the temps about 10*c - 15*c. I knew I could do better so then I tried several different thicknesses of coper with an aluminum heatsink mounted on top and got similar results. Last I tried the one pictured and WOW, that was the result I was looking for! Idling in the 20s and 30s with no cooling pad!

I here is a pick of my temps as i'm typing. (This is with running a 22" monitor)

 

Here is a pick of the the mod that didn't work as well with with 1/4" copper and aluminum heatsinks epoxied on top. (Too thick of copper, not enough dissipation) Maybe the one your looking at (being of copper), will work better. I didn't see that one when looking but you are obviously better as finding things on the web than I am. (that's twice now)

 

Opps, sorry about the size of that one.

 

Without the 1/4" copper in between there was even less of a difference.

 

@Tanware: under normal high loads. Gaming et al.

Havent run Prime95 in ages. Wouldnt be surprised if it did cause overheating after 20-30mins from previous experience.

@Cacheflow: Impressive 24C idle lol. I take what i said back. The mod definitely works although i do echo previous posts with regard to the ESD shielding being compromised & the backpanel having a gaping square cut out of it to accomodate the modded heatsink. Otherwise, good job!

 

Yeah, this is why I am going copper. I idle 42c load with prime95 2.93 GHz eventually will overheat. I just want load 2.93 GHz to be prime95 and walk away stability & heat............

 

With the temps under controle I might switch to the x9100 so I can oc. I've read that I can get at least 3.54ghz out of that core. Or can I get more?
Isn't that the only difference between the t9900 and x9100, unlocked clock and 45w? (Is there a way to oc the t9100 now a days? most posts are from '08)

 

I could get 4.0 GHz 1.450 vCore but heat was a sever issue, maybe with the mod you can hold it there.......

 

yeah 4.0GHz @ 1.450V is possible but overheating occurs after 3-5mins in Prime95.

In terms of practicality, 3.7GHz @ 1.320V is probably the upper limit for what the stock HS can handle from my experience.

Did manage to maintain to run @ 4.0GHz under Prime95 for substantially longer with the help of some ice-cold solvent (from a can of compressed air) directed on the heatsink:
http://forum.notebookreview.com/gat...experimental-fun-do-not-casually-attempt.html

Would be very interesting to see if your modded HS is capable of handling 4.0GHz on its own!

 

Is there a bio and upgrade and a Clock Generator/PLL for the p7811fx motherboard to oc a t9900 yet? Most of the posts I've read are mixed and are from 2008. Trying to sift through 157+ pages 20 some odd post and still unsure.

 

I think to unlock the pll you need to do a hard mod. there is a bios mod to unlock EIST though......................

 

Got the Heat Sink today and AS Thermal adhesive. I just cleaned and did not polish it up. Before with the cpu pannel removed, Prime 95 @ 2.93 GHz and 95c where I shut it down on a 4 minute run. Now with the new heatink I maxed 91c after 15 minutes but mostly ran 88c on the one core to 82c on the others. Not a drastic change but what I was looking for.

Note all runs on top of a laptop cooler................

 

That is still a huge improvement. You'll be able to do more, longer without shortning the life of the unit.

Does the cover fit with the modded HS? What are the temps at idle with the cover on? Got any pics?

 

I tried again peak after 15 minutes 92c, cut the cover as it would not fit and placed it back without the shield now peak on Pime95 is 87c at 2.93GHz as the cpu fan now pulls air across it. The fins do not protrude out further than the cover...............

Edit; Idle was about 47c @ 2.93GHz it now is 41c at its lowest. TSZ went from 42c to 39c at idle.............

Edit2; actually inspecting it again there is a 1mm protrusion.............

Edit3; Gpu on furmark 10 minute run went up from 81c to 86c, still well within limits.

Need to clean up some more btu a couple of pics

 

Set that baby on a coolmaser cooling pad with the fan blowing directly on the cutout and you'll be golden.

You can get one of these to cover the hole or find one thinner without the filter. Micro Center - Bgears 80mm Fan Filter 2-Pack BG01374

 

Ran prime 95 for the first time to see how the mod HS would do.

Not sure what this means but I ran for 1hr 5min and here are the results:

http://i1228.photobucket.com/albums/ee445/CacheFlow123/NewPicture6.jpg

 

Awesome temps, as far as a fan cover I may go with something like this.

 

Yeh, your cutout is nice and square and it doesn't stick out much. It will be easy to cover. A little jb kwickweld and done. Mine will be a little more challenging. It's odd shaped and whatever i cover the heatsink with has to mount on the bottom cover so that the bottom cover can still be removed. Gonna have to fab or mod something to fit. Plus I want it to look nice.

I might head up to Microcenter and have a look-see what they have on the shelf that I can work with. There's one near me.

 

That iss why I wanted as little protrusion as possible, easy to remove and no leg extensions. With the caver even at 6mm I'll have to extend the legs a bit though..............

 

I am truly envious of the mods that you guys are doing, great work!

I'm hoping to grow a pair one day and start modding mine

 

While not overly extreme here I am happy with the subdued approach..........

 

Hi guys,

TANWare, if possible, can you explain how you modded the stock heatsink and added the enzotech one?

Thanks in advance

 

The new HS is almost the exact size of the standard section that goes over the CPU. I removed the tape pads and lable. Then fully cleaned it with alcohol and used AS GPU thermal adhesive on the aluminum andd copper that would contact the new HS.

Of course as you see I removed the fan and screws. put a dab of paste over each screw post then put the cover over so I had the location to drill the four holes on the plate and cut accordingly.

As a side note there are two copper tabs, I just pointed them along the same axis as the heat pipe so they did not have to get cut............

 

Just imagine the horror stories people will have if they actually place the LAPtop with this mod on their LAP.

Keyword: lap.

 

yeah, I know mine can get a bit toasty...........