Graphics card memory interface speeds (448 0ver 256) ???

[mricham]

hey everyone im looking at getting a new g card

one thing i have see is that my gtx 260 have a very good mem interface

Memory

Memory Size896MB
Memory Interface448-bit
Memory TypeGDDR3

how much dos the mem interface play with speed at all the new cards have 256

only the very high end cards have the 512

"MSI® nVidia GeForce GTX680 Lightning Edition PCI-Express x16 3.0, GDDR5 2GB, 256-Bit, GPU:1110MHz / Mem:6008MHz, DVI x2, DisplayPortx1, HDMI x1, DirectX 11
Dual Slot ATX, MSI Afterburner, All Solid Capacitors, Blu-Ray Support, NVIDIA CUDA, NVIDIA PureVideo HD, PhysX by NVIDIA, 3D Vision Ready, 3-Way NVIDIA SLI Support"

"MSI® nVidia GeForce GTX690 PCI-Express x16 3.0, GDDR5 4GB, 512-Bit, GPU:915MHz / Mem:6008MHz, DVI x3, Mini DisplayPort x1, DirectX 11
Dual Slot ATX, MSI Afterburner, All Solid Capacitors, Blu-Ray Support, NVIDIA CUDA, NVIDIA PureVideo HD, PhysX by NVIDIA, 3D Vision Ready, 4-Way NVIDIA SLI Support"

in short
if anyone know why this mem speed is so much better on my (old and trusted msi gtx 260 oc edition)

 

[drums101]

its always been a sore spot with me that nvidia has been only putting 256bit memory busses on their cards...but I guess they do that because they found out they really dont need to make it any bigger...but the reason why the 690 says 512bit is because its a dual gpu so its 256x2....a 690 is basically two 680s slapped together with their clocks dropped a little...so long story short just because the memory bus on your older card is bigger doesnt mean its better