Precision 5550 Overheating

The company I work for has several Precision 5550's and they have been nothing but problems from day 1. The most common problem we have is that they are overheating in sleep mode and sometimes while we use them. they get hot enough so that they shut down. I keep mine sitting on two 6" fans on full blast to help keep it cool. we have had these computers for approximately a year. So far we have had a couple of them literally burn up and have had to be replaced. If I let mine sit over night without turning it off and it goes into sleep mode sometimes when I come in the next morning it is hot enough that you cant hold onto it, even with my added cooling fan. I will have to unplug it from everything and let it sit on the fan for a couple of hours to cool off enough so that it will power back up. We have tried replacing the docking stations with new ones but it does not seem to make a difference. Our IT department has not received a solution from Dell about it so they just consider it a non issue. The general consensus among those of us that are using these computers is that there is a design flaw in the computers and Dell is refusing to admit it because they don't want to replace all of these computers. Anyone else have this issue?