if it's a standard size power supply... which i'd hope it would be (unlike my stupid Sony Vaio that used a small form factor PSU which was about half the size of a normal one), i'd have to say the Ultra X-Connect modular power supply. 500 watts for i think around $100, maybe a little less. haven't had a single problem with mine, and they make the inside of the case look pretty tidy.
in my experience with dell(I had an 8250) they use a "special" dell version of a power supply. They make adaptors that will make retial ones work, I could never find one. What are you needing that much power for? what are your specs?
Check the label on the side of the Dell Power supply. You are looking for the power rating in watts (not that important) and the current rating on the +12V, +5V & +3.3V outputs (very improtant). Post the numbers in the thread.
Also, see if the PSU label says "ATX standard" on it anywhere. That will tell you it is standard size. Dell has gotten better about non standard power supplies in the last few years.
Dell usually puts pretty robust power supplies in so you may not need an upgrade. On the other hand if any of that hardware was not bought and installed by Dell they will void your warantee, so getting a new PSU whose manufacturer will replace the PC is it gets fried may be a good idea.
OMG - never mind I pulled the 8300 specs:
Output Wattage: 250 Watts
Input Voltage (auto-sensing): 90 to 135V at 50/60 Hz; or 180 to 265 V at 50/60 Hz
Heat Dissipation: 853 BTU/hour (fully loaded computer without monitor)
Backup Battery: 3.0 V CR2032 coin cell
The backview does look like a standard ATX power supply, not the mini.
heh. yah, he's DEFINITELY gonna need a beefier PSU to handle the video card. Think i already had a card get killed by undervoltage. PSU in my Vaio wasn't providing enough for my GeForce 4 Ti4200 and.... well..... woke up the one morning with a screen full of artifacts. needless to say, i restarted the computer over and over with the same result, then on the last try, it just stayed black. *sobs* still have the card sittin in the box in the corner of the room.
well, usually if you get a good quality well known type/brand of PSU, u probably wouldn't have to worry about doing all that since the company might have already done so to make sure it's working the way it should. now if you get one from some back alley shop that just opened and has a sign in front of the PSU that says "works good", THEN..... u might wanna take the extra precautions.