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FREE SOFTWARE GIVEAWAY

We have 4 x Pro Licences (valued at $59 each) for 2d modular animation software Spriter to give away in this Thursday's GDNet Direct email newsletter.


Read more in this forum topic or make sure you're signed up (from the right-hand sidebar on the homepage) and read Thursday's newsletter to get in the running!


#ActualHodgman

Posted 16 January 2013 - 06:05 PM

In general, memory bandwidth is improving at a slower rate than processor arithmetic speeds are improving.

In relative terms, over the years, the amount of memory that we can transfer in the same time as one CPU clock-cycle has actually decreased!

 

All the same issues apply to GPUs -- bandwidth often becomes the bottleneck instead of ALU cycles. Using smaller data formats can often give huge speed boosts -- as above, mip-mapping is kinda-sorta a form of data compression for the case where you're viewing a texture at a distance wink.png

 

It's also interesting to look at the specs of cheap vs expensive models of video cards -- often one of the things that separates them is an order of magnitude difference in their memory bandwidth! e.g. picking some nVidia cards:

GeForce 205 -> 8 GiB/s

GeForce GTX 285 -> 159.0 GiB/s

 

Your high-end users can process a hell of a lot more data per frame than your low-end users can, which is why the low-end cards will have to use lower-resolution render-targets and textures, lower vertex counts, etc, etc...


#2Hodgman

Posted 16 January 2013 - 06:04 PM

In general, memory bandwidth is improving at a slower rate than processor arithmetic speeds are improving.

In relative terms, over the years, the amount of memory that we can transfer in the same time as one CPU clock-cycle has actually decreased!

 

All the same issues apply to GPUs -- bandwidth often becomes the bottleneck instead of ALU cycles. Using smaller data formats can often give huge speed boosts -- as above, mip-mapping is kinda-sorta a form of data compression for the case where you're viewing a texture at a distance wink.png

 

It's also interesting to look at the specs of cheap vs expensive models of video cards -- often one of the things that separates them is an order of magnitude difference in their memory bandwidth! e.g. picking some nVidia cards:

GeForce 205 -> 8 GiB/s

GeForce GTX 285 -> 159.0 GiB/s


#1Hodgman

Posted 16 January 2013 - 06:03 PM

In general terms, memory bandwidth is improving at a slower rate than processor arithmetic speeds are improving.

 

In relative terms, over the years, the amount of memory that we can transfer in the same time as one CPU clock-cycle has actually decreased!

 

All the same issues apply to GPUs -- bandwidth often becomes the bottleneck instead of ALU cycles. Using smaller data formats can often give huge speed boosts -- as above mip-mapping is kinda-sorta a form of data compression for the case where you're viewing a texture at a distance wink.png

 

It's also interesting to look at the specs of cheap vs expensive models of video cards -- often one of the things that separates them is an order of magnitude difference in their memory bandwidth! e.g. picking some nVidia cards:

GeForce 205 -> 8 GiB/s

GeForce GTX 285 -> 159.0 GiB/s


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