I keep saying I am going to format my 4550 and install my unused $39 "Go Pro" copy WinXP Pro but I never get around to it. Even with all the standard Dell junk on the system with their XP Home install, the system runs amazingly well. I have not had a single issue yet in terms of stability or usability. I would buy the system again with no hesitation, the only change I would make is getting the primarary drive as a 40GB instead of the 20GB I ordered. The 20GB ended up being a Seagate Cuda IV so I can not complain too much though.
As far as changes I have made to my system... I sold my 256MB stick of Kingston RAM and returned my original 128MB stick to Dell for credit. Dell credited me almost $100 for the 128MB stick! Now I am running just one stick of Kingston PC2700 512MB. I flashed the BIOS to A02 and found the Dell flash utilitiy is quite nifty.
Here is another tip to anyone adding extra drives. To avoid issues, set the primary drive to the primary jumper and leave the remaining drive on cable select. This sounds pretty simple, but I have seen a few post on the Dell forums where this was an issue. Going with primary one one drive and cable select on the other seems to have no issues in any config on anyone's system. Also, make sure you set those CDRom channels to use DMA, it really helps anytime you need to use the drive.
The 4550s support Hyperthreading CPUs as well in case anyone cares. Not sure about the heatsink though, I am not going to be the first to try a 3.06HT chip with a passive heatsink and heat shroud for exhaust
