Cpu fan always on high

Your complete system specs and your CPU temperatures please.

How about temps ? Is everything OK with fans etc ? Nice and clean ? Sounds like either overheating CPU or faulty RAM to me...What if you try 1 out of all sticks ?? Try memtest and see if it reports any problems...

ok i have found out that the cdrom was causing the hang up on the bios I ran pc doctor service center 7.5 again and the cdrom failed the test. But the fan still speeds up I have also noticed that the power light comes on when the fan slows down but when it is constanly going the power light on the front of the pc is off but the pc is on. All my RAM have passed different test. A little background on me I am A+ cert. so I have tried all the usual test. I am wondering if the thermal paste has worn off. Ok here are the specs requested.
Intel® Pentium® E2160 (Dual Core) processor
Intel 945G chipset
3072 MB DDR2, 667 MHz, (PC2-5300) dual channel memory (two 1024 MB and two 512 MB modules)
400 GB, 7200 RPM, SATA II hard drive
Intel Graphics Media Accelerator 950
Upgraded the PSU to 400 watts
uATX Motherboard 4006244R

Oh and temps are in normal range according to the Bios, speedfan, and everest. This computer really has me confused.

and something else that I have now noticed if I run the pc in safe mode the fan is on high for like 5 to 10 mintues and then goes to normal speed after that no matter what I am doing. The fan will not return to normal speed when it is not in safe mode.

First, have you opened the case and cleaned out the dust from the heat sinks? What are the temps, exactly?

Second, are you sure that's the CPU fan, and not the CDROM spinning up?

Yes the case is completly clean heat sink fan psu everything is clean, the temps range between 40 to 42C, and yes I am sure its not the cdrom cause i have completely removed the cdrom and it still makes the same noise.

Did you try reinstall all relative drivers, such as chipset acpi etc?? The thing that puzzles me though is that in safe mode throttling works OK... And usually these things are controlled in BIOS... Have you installed any particular fan controlling software ? If so uninstall everything relative to that and see how it goes... Anything that can control fan speeds...

Has freezing been fixed ??

No freezing has not been fixed when I am in normal windows mode, and I will uninstall Speedfan and see but it was doing it before I installed it. As for as the drivers no I havent tried that but I will.

Ok so I unistalled Speedfan and all other fan software but it didnt change anything. I also tried reinstalling the drivers but no change there. I guess this has others stumped also now I dont feel so bad now cause this is my mom and dads computer and my job is to fix computers everyday and I cant fix theirs.  

Well computers are chaotic and every once in a while you are bound to stumble upon something weird which you can't figure out and also even when you solve it you realize it doesn't make sense anyway...

Sorry I can't be of much help here, but if I was you I would try to keep stuff at absolute minimum meaning that:

1) since you have 4 DIMMs I would remove 3 out of 4 and leave 1 stick GB inside. IME many times RAM keeps passing tests but that doesn't mean it's not faulty. If freeze ups persist I would try once the other GB module and see how things go.

2) I would remove all unneeded stuff, USB devices, unneeded components inside case etc

If problem was solved I would go on and try to reconnect devices etc and see if I could isolate the problem...

For the fan speed problem I would reload BIOS defaults, check BIOS q-fan/speedfan settings and try a basic OS installation somewhere to see how it behaves...