Crackling Sound coming from MB (hard drive died..)

[esadb]

So i removed the logic board the other night from the macbook to inspect a charging issue. Put it all back together. This is a C2D 2.1ghz, 1gb ram, 160gb hdd, Mid 2007 model.

Just last night i did an update as i installed a fresh copy of leopard on the machine and then all of a sudden this Crackling sound starting coming out from the top left corner..

It appears to be where the speaker is.. and right above where the fan is for the CPU.

Now the logic board stayed out of the machine for a few days and when i put it back on.. i did not put any new thermal paste back on the cpu dyes.. Should i have?

Now the macbook starts up.. makes the crackling sound.. and it just sits at the Apple logo and seems to boot forever never finishing the boot..

Anyone have ideas? Is it perhaps that i should have applied new thermal paste and the thing is now overheating?

 

[blackburn]

No thermal paste -> cpu overheating -> high fan noise.
I highly recommend installing thermal paste before assembling the heatsink.

 

[iThinkergoiMac]

Yes, thermal paste is an absolute necessity. I recommend getting the old paste off first, using either an official thermal paste remover or some rubbing alcohol. Arctic Silver 5 is a great option.

 

[esadb]

After spending 2 days and putting new thermal paste on turns out the hard drive just died I guess..

I see it in disk utility when i boot from the leopard disk. But when i tried to format or repair the disk it just says "Cannot Allocate Memory"

I tried hooking it up to my windows machine and running hdat on it to repair bad sectors without much luck. Guess the hard drive just crapped out..

Luckily I had another 60gb kicking around i put in the MB and now im back up and running on it. And now back to the charging issue i have with this machine..