Hello,
 
Just purchased a new Dell Inspirion, and would like to know whats the best/fastest video card that I can install.  I know the power supply is limited to 300w and the bus is PCI express x16.  Can anyone help?

Check the amperage on the 12V rail.  Assuming there is no PCI-E connector, you can probably get an 8600GT for it without too much trouble.  If you prefer ATI, an HD2600 ought to work.  The XT is faster than the Pro, but I'm not sure of power requirements.
 
I'm assuming the mobo has a PCI-E slot on it...

Thanks for the help.  The 12v rail amperage is 18amps.  There is a PCI-e connector.   Is the 8600GT or the HD2600 the best I can do?
 

Dell under rate their psu's by alot...
 
You can put a 9600gt/HD3870 in that pc no problem..
 
I had a Dell Vostro 200 with same psu as you and I had a 7950gt and later HD3850 and it worked perfectly
 
You will need this adapter
 
As your dell doesnt have a molex power connector...
 
http://www.performance-pcs.com/cat [...] s_id=20580
 
http://www.dellcommunity.com/suppo [...] 05#M171498
 
http://www.dellcommunity.com/suppo [...] 57#M122077

I just did a similar thing... I have a dell demension with a power supply similar to yours. I chose the 8600gt and it works great. The reason I chose this card is simple. You should be able to install it without upgrading your psu (power supply unit). Unlike more powerful cards such as the 8600 gts or the 8800 series you don't need an extra power cable to power the card. It draws power directly from the pci-e slot. (the 8800 series is probably overkill unless your doing a MAJOR upgrade to your system) The 8600gt definitely improved my performance. (the former card i had was an ATI x600 256mb hypermemory.... avoid this card like the plague!)

You have 22amps
You could go with a 8600GTS or 7950GT or 9600GT.
If you have a spare molex you can use this:
 
http://www.newegg.com/Product/Prod [...] 6812201004