Replacing CPU Cooling Fan / Heat Sink Assembly

The CPU cooling fan on my hp envy 15-1100T is starting to make some noise that sounds like the bearings have deteriorated and need replacing. Also occasionally when booting I get a BIOS error message indicating there is a problem with the CPU cooling fan and the laptop won't start.

I've ordered HP part 576837-001 processor fan and thermal heat sink assembly from China



I know how to open the laptop chassis and clean dust from the interior, replace hard drive, etc., but I've never attempted anything more elaborate like thermal repaste.

Is it relatively simple to replace the CPU fan and heat sink assembly? Or should I take it to a professional and have them install the replacement part?

 

I'd say it's pretty simple, but you have to clean the old paste off the CPU and GPU using isopropyl alcohol and apply a new one, you'll find a lot of guides here on how to apply thermal paste.

 

Thanks MPIX! I opened up the laptop and it does seem simple to replace.

I noticed that one of the fans seems to work just fine but the second one does not move at all.

 

You are referring to the old fans or the new ones? Let us know how it went.

 

Just received the Cooling Fan assembly and thermal paste, gonna try to do this tomorrow.

The main thing I'm worried about is applying the paste correctly. Do I make one small bead in the center of the heat sink surface? I have also heard suggestions to make five beads (one in each corner, and one in the center) or other suggestions to spread it out evenly with a credit card.

EDIT: here is a guide I found - does this seem like good advice? http://www.tomsguide.com/us/Laptop-Notebook-Overheating,review-1596-9.html

 

If your chip is rectangular, use the line method. If it's square use the dot method, and let the pressure of the heatsink spread it. Do not touch the paste with your hands and never use the credit card method, it leaves a lot of air gaps. Also make sure to have the chips and the heatsink cleaned before applying thermal paste ( preferably with alcohol ) to completely remove the traces of the old paste.

I attached a picture for the line method on your CPU ( i7 820QM ). Good luck!

 

A line or an X pattern is usually the best. Multiple dots/beads do not seem like a good process.

 

Wow, thank you both so much - awesome to be able to see this correctly applied on the same processor!

One more question - OK to use 97% isopropyl alcohol to clean the heat sink and CPU?

 

160 Proof Vodka is better - you can drink whatever is left over.

J/K!!!

Yeah, 97% isopropyl alcohol is good.

 

97%, not enough.

Spoiler

Seriously, 97% alcohol is fine. Technically, you could even use water, it just takes forever to dry and isopropyl alcohol is a better solvent for the TIM as far as I know anyways.

I also agree with the line method, a dot is nice for a square sized die, but if it's a rectangle, a line is better to ensure there is uniform TIM on the whole surface.

 

Do I need to buy some kind of toothbrush or something to clean the CPU?

The guide I read just suggested using an old credit card to scrape the old compound off, and then wipe it with lint free cloth. Another guide suggested to use Q-tips soaked in alcohol.

 

Who's ready for some shots? =P

 

Unfortunately, isopropyl alcohol is toxic. I do have anhydrous ethanol, the kind you can drink, in the lab though, but no picture and it's a whole gallon. It would also clean TIM pretty well.

 

Just make sure you don't put too much, that it comes out on the side.

 

Wow, thank you guys so much, can't believe I actually managed to pull this off!

When opening the case and fiddling around, I was trying to be very careful not to damage any components. Felt a bit like the game "Operation"

One thing that I wished I had asked about before turning off the laptop was how to remove the small cable connector for the fan power supply. There was resistance in pulling it out, and initially I wasn't sure if I needed to press some tiny button on the connector to release it without damaging the parts. Slowly wiggled it a bit and eventually it came out.

Don't have any temperature monitoring software installed, but I can certainly feel a massive difference in the external temps of the chassis, and most importantly, the laptop now boots promptly. (Previously I avoided turning off the laptop as the CPU Cooling Fan Error prevented it from booting for up to an hour or so.)

I never would have attempted anything like this if it weren't for being inspired by the comments I've read here in NBR over the years about repasting and various modifications.

I imagine if I had taken it to a repair shop, it would have likely cost a few hundred dollars, which I couldn't justify spending on such an old laptop.

 

Happy everything is working out.

Connectors can be somewhat delicate it's true and some need to be pulled, others are like latches that have to be flipped (usually ribbon cables). If you ever end up messing with another laptop and you're unsure, you can always take pictures and we'll do what we can.