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[edgar]

double or single precision?

In your document at http://ati.amd.com/technology/...ting/AMD-ACML-GPU.pdf

it states on page 3: "Single ATI Radeon HD 2900XT or AMD FireStream 9170 (required for double precision)".

Does this mean the Single ATI Radeon HD 2900XT does onlf SINGLE precision?

[MicahVillmow]

The ATI Radeon HD 2900XT does not support double precision operations. Consumer level cards that do support double precision are the ATI Radeon HD 3850 and 3870 cards.

[edgar]

So this means I can do, say, double precision floating point Monte Carlo simulations using a ATI Radeon HD 3850 or 3870 card?

[MicahVillmow]

Sure, there are no restrictions from our side preventing this that I know of.

[edgar]

Can't wait to start. What CPUs are there to select from? Which 3870 card is best? Which motherboards are apprpriate? -- I prefer ASUS.

Thanks, Bill

[MicahVillmow]

Although we don't limit our SDK to a specific CPU, motherboard or Radeon card manufacturer, AMD does provide an integrated solution in the Spider platform(Phenom CPU, 790FX chipset and 3850/3870). So you can choose the company that you like to provide the hardware for you.

[edgar]

Including the Tri-core Phenom?

[michael_chu]

I don't see a reason why our SDK wouldn't work on the tri-core phenom. However, it would have to be tested for us to officially support that configuration.

Michael.

[edgar]

Any idea what would be the speed loss of using a 3870 vs the FireStream. If Firestream is three times as fast than the 3870 at doing double precison Floating Point calculations, then I would rather wait and work using the FireStream system. Comming out next month I hear?

[michael_chu]

The FireStream 9170 will have 2GB vs. the 512MB on the Radeon HD 3870. This will allow certain applications to run faster in their data set size would have exceeded the 512MB available on the 3870. It reduces or eliminates the need to traverse the PCIe link to load/unload data multiple times. The raw DP floating point calculation speeds are going to be comparable from the 3870 to the 9170. But raw FLOPS isn't always the final indicator as to how fast the entire system will run.

If you already have a Radeon HD 3870, I'd recommend going ahead and developing on that. As you develop your application, you will be able to see where the system level bottlenecks are and decide if the 9170 makes sense for your application.

The FireStream 9170 also has other advantages such as longer warranty period/support which are important in certain commercial deployments as well.

Michael.