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Old 09-22-04, 07:59 PM   #15
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Default Re: All 3dmark05 test to utilize SM3.0

Originally Posted by Pandora's Box
hmmm. it doesnt utilize sm3.0. it uses fp16/fp32. not full fp32 which is a requirement of sm3.0
A SM3.0 card only has to be able to do FP32, not use it all the time. Partial precision FP16 is allowed in the DX9.0c spec's for SM3.0. So using both FP16/32 is still fully SM3.0 compliant.
This is a cut and paste from the SDK.

Shader Model 3 

Specifying Full or Partial Precision 

ps_3_0 (and ps_2_x) provides support for 2 levels of precision: 

Full fp32 or higher 
Partial precision fp16=s10e5 

Full fp24=s16e7 or higher 
Partial precision fp16=s10e5 

ps_3_0 supports more presision than ps_2_0 does. By default all operations occur at the full precision level. 

Partial precision (see Modifiers for ps_2_0 and Above) is requested by adding the _pp modifier to shader code (provided that the underlying implementation supports it). Implementations are always free to ignore the modifier and perform the affected operations in full precision.
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Last edited by rellingsen; 09-22-04 at 08:19 PM.
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