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GPU Memory Interface

post #1 of 5
Thread Starter 
The GPU Memory Interface Questions

So, Hopefully some people here can shed some more light onto this topic, and hopefully provide some use cases with current technology and cards.

The Question:
Can someone put down some solid facts and information about the memory interface of a GPU. For example, 192Bit vs 256Bit, but also the VRAM size behind this, for example;

4GB GDDR5 on 192Bit Memory Interface
4GB GDDR5 on 256Bit Memory Interface

Can all the VRAM actually be used in a timely manner? Doesn't this cause FPS issues as smaller interfaces have double sided ram chips sharing the same 32Bit interface into the memory controller?

The reason I ask this is, that we are seeing more cards such as the GTX760 with a 256Bit interface coming out with 4GB variants, can this VRAM really ( I mean really ) be used?

If people have some additional questions for this topic, lets actually get a good list and discussion going here, feel free to PM me.
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post #2 of 5
All it is is memory bandwith. 256 is what most cards have. New Radeons are rumored 512 bit so go figure
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post #3 of 5
It comes down to bandwidth. The bit-width multiplied by the effective memory frequency is how much data can be moved back and forth.


How much memory is available and being utilized is slightly different. It's not like all the memory is being utilized for a single process at once. It's the same way with main system RAM.... one application is not using the entirety at once. Chunks of data are getting read/written to as needed by the processor(s).
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post #4 of 5
This review addresses your question. Say what you will about Tom's I thought it was pretty good.

http://www.tomshardware.com/reviews/geforce-gtx-660-ti-memory-bandwidth-anti-aliasing,3283.html
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post #5 of 5
Thread Starter 
Quote:
Originally Posted by lightsout View Post

This review addresses your question. Say what you will about Tom's I thought it was pretty good.

http://www.tomshardware.com/reviews/geforce-gtx-660-ti-memory-bandwidth-anti-aliasing,3283.html

Thanks! As I thought, the additional memory controllers cause latency and can perform worse.
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The Claw
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