well, besides the upgrade from pny -> bfg...
the 7800gtx requires additional power (pci-e 2x3(6) pin connector) which means it pushes performance faster than the 9400gt.
the x400... means a lower class than the x800... class. which means more power.
not sure about the technical specs... been trying to figure it out.
but i played a quick skirmish (c&c generals) and i nuked my shit in their base... nearly no lag at all (7800), versus the slight glitching with the 9400.
memory
capacity/type: 256 gddr3 vs 512 ddr2 (7800 vs 9400, respectively)
interface(bits): 256 vs 128
bandwidth: 41.6 GB/s vs 12.8 GB/s
clocks (7800 vs 9400) :
core: 460 vs 550
memory: 1300 vs 800
(7800) 920 million vertices per second vs (9400) 4.4 billion pixels per second
- not sure how this comparison works out, as I cannot find the similar spec for the other card -- ie, I cannot find a pix/s count for the 7800.
(7800) 24 pixel pipes vs (9400) 19 stream processors
- I do not believe these are comparable, but they are the closest to the things I want to compare.
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main reason: better class (may be a generation or two older).
no, scratch that.
I wanted a Big Fucking Gun. :ninja