Might I suggest going 32 bit, ditching 2 gigs of the ram and spending that on a 4850? Also, the E2200 isn't the latest greatest... Assuming prices are similar to here; 500E = 500USD: you should be able to get better hardware. Assuming general costs are roughly 180E / 150 E that leaves us 350E.
4850: 130E
4gig mem (total): 28E
CPU: E7400: 120E
Now I could be miscalculating here, but this leaves (out of the 500E) 222E. Surely that is enough to buy the other components?
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Reading through the topic again, I can say my suggestion might be a bit tough graphics wise. Regardless though I'd stay 32bit (and go down to 4 gigs total, more then enough) and upgrade the CPU. The E2200 is pretty crippled. Also, salvaging anything you still have left is a great way to bring down costs (for example getting the casing is a great thing to leach from somewhere, same goes for HD, though that can cut performance).
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A steal, though not sure how the warranty works out:
(link snippeded)
But a nice price non the less!
This is a pre-built computer (it's open box, I get about 30% off), so ditching 64-Bit won't be cheaper.
Here's what the computer looks like without me upgrading anything.
QUOTEDell Inspiron 518, E2200 (2.2GHZ)
16X DVD+/-RW DRIVE
2GB DDR2 SDRAM AT 800MHZ
320GB SERIAL ATA II,7200 RPM,DIM,M
Dell USB Keyboard and mouse
Vista SP1 HOME PREM 64-Bit
DELL E198WFP Widescreen LCD, 19"
WARRANTY ENDS 10/7/2009
Cost: $500