I am experiencing the same problems...
Hello,
We have about 70 of these machines at our workplace. Must be said that we have had a lot of problems with these machines.
Performance wise, they are very good. Ours are 2.8GHz Pentium 4's with 512KB L2 cache and an 800MHz FSB. It does the job very well, especially in our Customer Service department where space is a real constraint.
One of the problems we have had is where the capacitors keep blowing. One of the Dell engineers told me that this was a problem where Dell bought a dodgy batch of capacitors and put them on the motherboards. They explode all the time! We replaced about 10 systems motherboards last year because of this problem. Just a phone call to Dell Support is all it takes (0870 908 0800).
Apart from that - damn do these machines get HOT! I decided to take the side off my machine to see what was making it get so hot... The fans on the bottom blow the cool air up through a channel created by a plastic cover over the CPU HSF, which seems ideal. Right above this is the NB HS, which is black in colour, at least on my motherboard (Dell told me that they occasionally change the design of their motherboards because of things like heat dissipation, or just bad design).
The black heatsink on the northbridge is too hot to touch for more than a few seconds!
It would be interesting to know if there is a way to increase the voltage running to the fans on the bottom of the computer. I understand that they get faster and louder as the processor gets more load. It does indeed get very noisy, but surely if it was like that all the time it would stay cool?
If they could possibly be upped by 50% it would improve things a lot.
I'll try to attach a photo of the system from the side when I get home from work.