MP 3,1 880GT Fan Going NUTS - Help!

[Michael73]

Within the last 2 days the fan on the card is going nuts! It ramps up and down for no reason. I can even shut the whole machine down, restart and let it sit there at the login screen under no load and it will alternate between normal quiet operation and full speed. WTH!

Any ideas? How can I fix? Need help ASAP. This is my work machine.

 

[Michael73]

Took the side off the computer while it's running. It's the nVidia 8800 gt fan.

I went to nVidia's website and downloaded and installed the latest set of drivers and that didn't help.

Thoughts?

 

[bax2003]

First and easiest thing to do is to clean it. Remove the heatsink, put some new thermal paste (Arctic Silver 5 for example) and clean heatsink thoroughly.

 

[MacVidCards]

Be very careful.

The reason these cards die is Nvidia used wrong solder in early years of "lead free"

It is very brittle and breaks under the GPU chip.

The very act of taking fan off will likely kill the card unless you are very careful not to flex it.

Best first step is a can of compressed air to blow BACKWARDS through fan. (ie, against normal direction of airflow)

Knock the dust bunnies out. I have seen these fans many times end up with a complete blockade of the fins inside.

 

[Michael73]

Be very careful.

The reason these cards die is Nvidia used wrong solder in early years of "lead free"

It is very brittle and breaks under the GPU chip.

The very act of taking fan off will likely kill the card unless you are very careful not to flex it.

Best first step is a can of compressed air to blow BACKWARDS through fan. (ie, against normal direction of airflow)

Knock the dust bunnies out. I have seen these fans many times end up with a complete blockade of the fins inside.

I actually had this problem maybe a year ago and gave the entire machine including the fan a good blow job and then everything seemed to work fine until a few days ago. However, I did the same thing before posting and the compressed air trick didn't seem to work

Anyway, it's currently at the Apple store for testing. If anything I'm hoping it's *just* the video card and not something like a temperature sensor on the logic board. I'll replace a video card but I'm not dumping that much $$$$ to replace a logic board in a 5 year old machine.

So here's the crazy thing...the guy at the Genius Bar says that the cost to replace my 8800GT is $279 but when I looked at the Apple Store online the newer and better Radeon 5770 is $249. Can anyone tell me why, if I need to replace my video card, I shouldn't upgrade in the process and save myself $30?

My MO all along was to work on this machine till the rumored new MP comes out later this year.

 

[Michael73]

Update...

Well, it only took the store 2 1/2 days to tell me the same thing I knew all along - the 8800GT is bad and needs to be replaced.

Make a long story short, I'm having a Radeon 5770 shipped to the store (it's supposed to arrive 4 earlier than at my house) where I'll make a genius bar appointment and they'll install it for me, for free. I'd do it myself but if I have to go the store to pick up the machine anyway, the card gets there faster and they'll do it for free, why not?!?

Anyway, does anyone know whether I'll notice any performance improvement between the 8800GT and the 5770?