Need help fixing FRIENDS iBook G4 800, freezes after a minute

Not a victive of the cracked chip, took it all apart.

Fan doesn;t go on but once when it first boots, the heat sink is not to hot when it freezes, sat next to a AC (cold) with bottom/top exposed, got a little more time.

Took out the RAM and used the onboard, same end result, RAM is fine, HD is fine, something is freezing due to temp.

I also tried to install a fan program, for 10.4, and it installed but when I click on it in the system preferences, it won't run,

Any ideas what it could be? All chips look fine, especially the known CRACKED issue chip, that is fine, all pins fine. Also noticed that one time, after it was frozen, it moved again for a few minutes.

Appreciate advice.

Update: Its for sure heat related. When I sat in front of thecair conditioner, with the bottom off and exposed, it ran almost 10 minutes. I then get the G4 fan control and had the fans running full blast but it still froze after a few minutes. If I rebooted I normally got a blue screen. If I held it near the A/C, it would boot normally.

In addition, I checked the chips that were known for cracking, none were found. Something tells me maybe the paste under the hear sink is dried up or there is a lose wire. Thing is, taking off the hear synch requires a special type if mini ratchet as the torxe 6 is not what is holding it down. Sure, there areca few screws but there are two special nuts and bolts holding it down.

Appreciate any help in diagnose.

Also a payer needed. Very sick. Adrenal gland working at 25% as my body is in so much pain. Also pray Blue Cross approves the prior authorization so I don't have to pay so much and only two pharmacies have the right ingridiants that work, so pray these new pharmacies can order it so the medicine actually works and that my doctor doesn't get mad as the pharmacy is trying to save me money by making my prescription in a liquid form which will be cheaper than putting together #600 capsules and if it's processed as generic or brand, I can change my plan with no underwriting and save a bundle. Now working now. To much pain, economy, medicines nit working also take 100mcg if fentanyl patches every two days with testosterone injections every two weeks plus my wife of one year had o ly one ovary and we want many children.
Lastly, pray I get my unemployment check today or tomorrow. I made a mistake in the form and have to wait for a phone interview in October 20th and send good vibes/prayers that the checks start coming sooner then that as while it's very little, does help is pay for a few things.

Good vibes, prayers appreciated.

Thanks eveyine and let's get this iBook fixed.