$20-$30 bucks? It's like $50+ gap. an OC'd 320 will stomp a stock 640 as well, so you have to compare the same clocks.
Which clock speeds am I looking for? The core clock or the memory clock? Also, you said a 320mb OC'd would stomp a 640mb stock, can't a 640mb be OC'd (like a cpu) or is that something that we cannot control? I don't know much about clock speeds I guess I need futher information about this stuff.
Which of these cards would be best for gaming? And would it still be very good in a year or 2? I am a thrifty type person and I want the most bang for my buck so I'll defer to the experts on which card is best for my situation.
-----------------------------------
PRICE: $329.99 (NO REBATE)
EVGA 320-P2-N817-AR GeForce 8800GTS 320MB GDDR3 PCI Express x16 KO ACS3 HDCP Video Card - Retail
Chipset Manufacturer: NVIDIA
Core clock: 588 Mhz
DirectX: DirectX 10
DVI: 2
Memory Clock: 1840 MHz (effective)
Memory Interface: 320-bit
OpenGL: OpenGL 2.0
Stream Processors: 96
TV-Out: HDTV / S-Video Out
VIVO: No
Model #: 320-P2-N817-AR
Item #: N82E16814130040
--------------------------------
PRICE: $284.99 (AFTER REBATE)
EVGA 320-P2-N815-AR GeForce 8800GTS 320MB GDDR3 PCI Express x16 HDCP Video Card - Retail
Chipset Manufacturer: NVIDIA
Core clock: 576MHz
DirectX: DirectX 10
DVI: 2
Memory Clock: 1700MHz(effective)
Memory Interface: 320-bit
OpenGL: OpenGL 2.0
Stream Processors: 96
TV-Out: HDTV / S-Video Out
VIVO: No
Model #: 320-P2-N815-AR
Item #: N82E16814130038
---------------------------------
PRICE: $319.99 (AFTER REBATE)
EVGA 640-P2-N821-AR GeForce 8800GTS 640MB GDDR3 PCI Express x16 HDCP Video Card - Retail
Last Month's Winner of Customer Choice Award - Video Cards
Chipset Manufacturer: NVIDIA
Core clock: 500MHz
DirectX: DirectX 10
DVI: 2
Memory Clock: 1600MHz(effective)
Memory Interface: 320-bit
OpenGL: OpenGL 2.0
Stream Processors: 96
TV-Out: HDTV / S-Video Out
VIVO: No
Model #: 640-P2-N821-AR
Item #: N82E16814130071
-----------------------------------
PRICE: $349.99 (AFTER REBATE)
EVGA 640-P2-N825-AR GeForce 8800GTS 640MB GDDR3 PCI Express x16 SUPERCLOCKED HDCP Video Card - Retail
Chipset Manufacturer: NVIDIA
Core clock: 576MHz
DirectX: DirectX 10
DVI: 2
Memory Clock: 1700MHz(effective)
Memory Interface: 320-bit
OpenGL: OpenGL 2.0
Stream Processors: 96
TV-Out: HDTV / S-Video Out
VIVO: No
Model #: 640-P2-N825-AR
Item #: N82E16814130080