Fuchsrohre

How feasible is it to replace the nforce2 heatsink on a PC motherboard ?

Mate told me his computer was crashing, so we opened up the machine only to find the nforce heatsink hanging loose on one side - on of the 2 retainers located at each side of the heatsink had snapped off.

I'm assuming, like a cpu heatsink, you can purchase a suitable heatsink and retainers easy enough for the nfroce processor?

I'll need to remove existing thermal paste and re-apply new. Any tips for getting the paste of the chip ?

Details: Motherboard MSI K7N2GM
http://www.msi.com.tw/program/produc...il.php?UID=437

I'm referring to the large silver heatsink below the CPU in this image:


I've located this product but I'm not keen on the thermal conductive adhesive tape which secures it to the chip ?
http://www.akasa.co.uk/akasa_english...pec_ak_210.htm

cong

use a hard plastic knife or your credit card!

Luminous

iTrader: (3)

Aha!! Something I know the answer to, as I have had to do this myself

I am going to assume that you have successfully removed the old Northbridge cooler (what you refer to as NForce 2 cooler). If not, release the plastic retainers first, then twist the cooler clockwise then anticlockwise until it releases.

On the chip you will find the remains of different kinds of paste depending on the manufactuer. Some are slimey, so they can be rubbed off with a lint free cloth. Others are hard, almost glue like.

If they are hard you can scrap the paste off. I use a penknife to do this, or you could use a small scraper. You are not trying to cut the paste off. Just gently scrape across the top of the chip until you have removed it all.

If you want to be pedantic, you then clean the top of the chip with some isopropylalcohol (sp).

A replacement cooler can be purhcased from www.quietpc.co.uk. You are looking for the Zalman Northbridge cooler.

Good luck

Fuchsrohre

cheers all

I can pick up the aforementioned Akasa locally, with its thermal adhesive pads - any good ?

Luminous

iTrader: (3)

The Akasa should be OK. Better to use paste than pads though. The Zalman allows you to do that.

All I can say is that I have an NForce 2 mobo with a Zalman heatsink. It works a treat. The Akasa probably will, but I have not used it...

Oh and the Zalman does not need a fan, so it will be nice and quiet

Fuchsrohre

ok, so I've removed, cleaned and replaced a the heatsink on the northbridge chip

looks like the northbridge has been damaged by overheating - can't get a display or even eject dvd drives. Power is getting to the board (fans rotating) but no display.

Looks like a new motherboard.

Luminous

iTrader: (3)

Hmmm. Even an improperly fitted heatsink should allow the power to come on and produce some sort of display for a while.

In case you have not already done so, its time to component swap. Reduce the machine to the bare minimum of components. No DVD/CD, no fax card, network cards or TV cards.

Just one HDD, one stick of memory, CPU (and Heatsink!!!), Video card and Power supply.

Retry turning the machine on. If it fails, swap one of the components and try again. Its time consuming

The motherboard may be OK, if it is, I would put my money on the GPU or PSU being the cause of the problem. I think that your diagnosis is probably correct from what you have said, but you can never be totally sure. After all, why was the Northbridge heatsink hanging off. If it had taken sufficient impact to dislodge that heatsink, then maybe the CPU's heatsink was also hit. Perhaps the CPU has taken damage <shrug>

BlkKnight

You should be able to do this without any of the boot process happening - even if everything is broken.

This would point me to PSU - unless the DVD drives are broken!

/edit - unless a cable has become damaged

Fuchsrohre

I noticed when I plugged the power cable into the back of the computer, it comes on immediately - with no display.

Luminous, you mention the CPU or GPU *probably* being the cause of the problem. With this being a nforce2 motherboard with IGP, isn't it fair to assume the GPU is located in the Northbridge chip ?

BlkKnight, regarding your PSU theory - so the cpu fan & northbridge fan are both going. This could still be the PSU ?

Also, when somebody mentioned the heatsink not fitting correctly would still allow the computer to boot - well I found the heatsink to not be in contact at all, it was hanging off one retainer (the retainer being a portrusion off to the side of the heatsink). If my mate has run it like this for a period of time, perhaps trying and trying again to get the computer working, isn't it fair to say the northbridge (incl GPU?) got fried ? If the northbridge DID get fried how would the problem manifest ?

Luminous

iTrader: (3)

Hiya - I don't think that it is probably the CPU or GPU, just a possibility.

If a component shorts out (rare, but it happens), mobo's just don't turn themselves on to try and limit damage. This is what happened when I had an issue with my Graphics card, the mobo would just not power up properly.

The fact that your fans are going does indicate that your PSU is capable of producing some power. Its just that a Power supply supplies power on different rails (normally at different voltages). Its possible for one of these to work, while others do not.

Most likely, the mobo is screwed. If you can component swap, do so. It may save you hassle in the future. If you do not have any spare components available my best guess is that the mobo is dead from what you have said.

Next guess would be a PSU related issue.

It is also entirely possible that when a component fails that it takes out other components in your machine. I had a faulty mobo take out the graphics card and power supply (along with the mobo itself). That was quite an expensive bill

This is why it is best to componet swap to see what is still working. Just check the components carefully before you put them into a working machine. If there are an signs of burning on contacts or other physical damage do not take the risk. Components that show signs of burning should be deposited in the nearest bin.

Fuchsrohre

cheers luminous, appreciate your time

Luminous

iTrader: (3)

Np, just hope it works out in the end for you