cypherslock :
Thanks Firepin. So that 16x is just the architecture, I won't have a problem physically putting it in?
I Had no probs as i was not using the other 2 pci slots and the heat sink on the 9600 is a whopper but it in fitted very comfortably you will not be running multiple video cards in SLI. You are NOT going to be doing that on your MCP73VE, which is a microATX motherboard with just one PCIExpress 16x slot.
Just a good-quality 400W PSU will already be more than enough to power anything you can possibly ever stuff onto that tiny micro ATX motherboard.
Your 9800GT draws a maximum of 105 watts, according to nVidia: http://www.nvidia.com/object/product_gef... (it's under the specifications tab.) 105 watts / 12 volts = 8.75 Amps.
Your Core 2 Duo draws 65 watts maximum. 65 watts / 12 volts = 5.5 Amps.
Rest of your system (1HDD, 1 ODD, mobo + ram) pulls 6 amps.
Your system pulls a little over 20 amps when everything is drawing max power at the same time (which rarely ever happens).
The Corsair 400W with 30 Amps on its +12V rail will already be way more than plenty for your system, with 10 Amps of excess capacity to spare. https://www.novatech.co.uk/novatech/spec...
A bigger PSU is NOT always better. PSUs run most efficiently when loaded to 60-70% of their rated output. At less than 60% load, A PSU is less efficient, which means extra unused capacity actually just generates extra waste heat.
Regards Firepin