ok i picked up a free dell dimension 8400 with a pentium 4 and 500 mb of ram and 160gb Hard drive so i turn it on and only sometimes it boots into windows xp home edition but almost every single time i try the fan starts spinning really fast and it gets super loud it gets almost as loud as my lawn mower some plzz help me!!!

 

Replace the fan!
Max.

 

Replace the fan!
Max.

ok i will try that

 

I predict a more serious problem, but we'll see.

How far along the boot progress does it get? Have you read your Event log?

 

I predict a more serious problem, but we'll see.

How far along the boot progress does it get? Have you read your Event log?

no the screen just goes black

 

no the screen just goes black

Do you know how to boot into BIOS (to avoid using the hard drive)? Or try booting from a CD or an external drive.

The screen going black could be many things. When in the boot process does this happen, early or late? For instance a very earlier failure could be bad RAM whereas a late failure leans towards the video card.

And keep in mind that, even if you succeed and get it working, it has virtually no value. Your local electronics recycling center may have ten machines similar to your's all in a pile. Know when to hold 'em, know when to fold 'em.

 

ok

 

The fan is probably fine. Depending on the model, many of them have thermostatically controlled variable speed fans, and when you first turn them on some of them will go full speed for a brief couple of seconds. If there's something wrong that's causing the boot process to hang, then the fan might get stuck at full speed. OR something is going wrong causing the CPU to get really hot, which in turn would cause the fan to go full speed. In any event, I suspect the fan going full speed is a symptom, not a problem. Clean all the dust off and then see if you can sort out the boot problems.

 

After neutralizing your body, pull all boards and re-seat. Memory, video....etc.

Then listen for post code.........beeps.

 

Hello,

With old systems, it can well be that dust has been collected in the heatsink.
Hold the fan and blowout the heatsink.
Also the fanspeed can be controlled by the motherboard.

Bertus

 

ok i put a new hard drive in i had laying around in storage and that fixed the fan prob but i still get no signal on the monitor so i replaced the ram but still no signal and then i got a old geforce4 card 64 MB out of a friends broken pc in my basement for repair i put it in the dell dimension and
i turned it on the graphics card fan did not even spin up so i think i need to dig around in a bunch of old computers for a working graphics card

 

Graphics card fans are typically not the highest quality fans, it's possible that the fan on your buddies card is just dead. Unless it was working while still in his pc..

If the settings in BIOS are not important to you, then it might help to restore the BIOS settings to the factory defaults so that you're starting from a known state. Sometimes you can select this option in the BIOS menu, sometimes there's a jumper on the motherboard to reset it.

 

Graphics card fans are typically not the highest quality fans, it's possible that the fan on your buddies card is just dead. Unless it was working while still in his pc..

If the settings in BIOS are not important to you, then it might help to restore the BIOS settings to the factory defaults so that you're starting from a known state. Sometimes you can select this option in the BIOS menu, sometimes there's a jumper on the motherboard to reset it.

already tried that but thanks for the suggestion later today i am brining the pc to my local computer store

 

ok i took the pc to my pc store and it is the motherboard

 

ok i picked up a free dell dimension 8400 with a pentium 4 and 500 mb of ram and 160gb Hard drive so i turn it on and only sometimes it boots into windows xp home edition but almost every single time i try the fan starts spinning really fast and it gets super loud it gets almost as loud as my lawn mower some plzz help me!!!

How many pins on the fan connector?

It could be sensing excessive temperature and running the fan flat out.

 

How many pins on the fan connector?

It could be sensing excessive temperature and running the fan flat out.

5 pins

 

5 pins

I've never seen more than 4 - 2 for the supply, a PWM control and a temperature sense wire.

 

Apparently Dell has dabbled with 5-pin connections
http://pinoutsguide.com/Motherboard/dell_5pin_4pin_pinout.shtml

 

Apparently Dell has dabbled with 5-pin connections
http://pinoutsguide.com/Motherboard/dell_5pin_4pin_pinout.shtml

You have to watch their PSUs as well - some of their 20/24 pin connectors have non standard pin assignments.

Usually; I avoid Dell stuff unless its free.