hi dear cadron,
i had some time ago the same dilemma....
i have an inferior specifications desktop than yours, a fujitsu esprimo p5730 and i wanted to upgrade too
since i am doing a lot of video editing and rendering, 3d bryce and gimp for photo edits i have decided for the follow upgrade
4 gb of ddr2 ram either 2 x2 or 1 x 4 dimms
a used pny geforce 9800 gtx or an nvidia quadro fx 3700
unfortunately my fujitsu's psu is too weak only 260 watts, the case is not too big so i have to install a low profile card even a geforce 7800 gs which is not bad at all
you can find and buy a geforce 9800 gtx for as low as 35 to 50 euros in great condition which still is a good card even by today's standards (games, video playing, photo edit, rendering 3d) but you need at least 500 watts ps with two pci-e power connectors
quadro fx cards are really top rated on pro apps like cad, 3d animation but geforce 9800 gtx is better for games
a good psu of at least 500 watts with an efficiency of 80+ will cost you as low as 45 to 80 euros
i forgot to mention that you can find through amazon or ebay a used desktop or refurbished with an intel pentium g840 / 860 socket 1155 at a very reasonable price, also an old intel core2 quad will do the job wih the adiition of some more ram and a good vga like those i have mentioned above
Edited by nickko, 13 February 2016 - 01:08 PM.