Dell have a tendancy to use back to front parts, or they used to. Thier power supplies were specifically designed for their motherboards as the connections were reversed on the 20 pin connector. I used to read a lot of people eplacing thier Dell motherboard and wondering why their new one fried, because they didnt know Dells PSUs were back to front. Dont know whether its still the case.
My PC is totally built by myself, and always will be as its cheaper and a PC is relatively simple to set up, and its a lot cheaper. I cant help but laugh when i walk into PC World and the guy says than an X400 GFX card will run any game on full settings, show the Crysis and they will retract that statement
My PCs:
-486, bought for £80 from my mams work
-AMD K6-2 550MHz, built by my dad as i was about 14 at the time
-AMD 2000, 512mb 2100 RAM, GeForce 4 MX420 GFX, built by me, my first PC i ever built
-AMD XP 2400, 1GB 3200 RAM, GeForce 4 Ti4200 128mb Done by me
-AMD 2800 Sempron, 6800, 1GB 3200 RAM, my 2400 fried and this was the only readily available chip
-AMD A64 3200 Venice, 1GB 3200, 6800 GFX Card, current rig, probably get a new GFX card when i start uni in Sept.