128bit vs 256bit

[Adam Redfern]

Hi, Would anyone mind explaining the difference between graphics cards with 128bit and 256bit, thanks 

[79wjd]

It's the amount of data that can be transferred into and out of the GPU. Don't worry about it when buying a GPU since it's largely an irrelevant factor (it's relevant, but it's not something which will tell you which gpu is better). 

[79 Potatoes]

Hi, Would anyone mind explaining the difference between graphics cards with 128bit and 256bit, thanks 

You mean vRAM?

Basically if the memory runs at the same frequency, a 256 bit bus will offer double the memory bandwidth over 128 bit

[Bob Jim]

You are looking between the GTX 960 and the R9 380 aren't you. Get the R9 380. Anyway, a wider memory bus=(sort of) higher bandwidth memory. But it really doesn't matter much for any modern GPUs, as far as I know no current GPU has a memory bandwidth issue.

[Glenwing]

It refers to the connection between the GPU and the onboard memory. A memory bus that is 256 bits wide can transfer 256 bits (8 bytes) of data to the memory every cycle. Combined with memory frequency, you can determine the overall bandwidth available for memory communication. For example, memory might operate at 7GHz (7 billion cycles per second) and at 128 or 256 bits per cycle, that's 896 or 1792 billion bits per second respectively, or 112 billion or 224 billion bytes per second, respectively. Or, 112GB/s or 224GB/s.

[Adam Redfern]

You are looking between the GTX 960 and the R9 380 aren't you. Get the R9 380. Anyway, a wider memory bus=(sort of) higher bandwidth memory. But it really doesn't matter much for any modern GPUs, as far as I know no current GPU has a memory bandwidth issue.

 

Actually yeah I am, I'm still undecided, thanks everyone for explaining and assuring me its nothing to worry about.

[Bob Jim]

Actually yeah I am, I'm still undecided, thanks everyone for explaining and assuring me its nothing to worry about.

R9 380 hands down. Better performance, same temperatures, similar features, and just a little bit more power consumption. Also do not bother with 4GB models, they are not worth it at all.