Question Please can someone tell me what Hawaii's rate of FP16 precision is please

[AshlayW]

I am writing a tech blog and I am trying to find out what speed Hawaii graphics processor (I.e R9 290X) can perform Half-precision calculations at, and is it throttled in the Radeon gaming cards.

I can't find it anywhere by my Google-fu skills are very lacking

Thanks <3

Ash

 

[AshlayW]

OKay I was told it is 1:1 of FP32 like all GCN GPUs pre-Vega (5th gen)

 

[IntelUser2000]

It's not all GCN GPUs. First support with GCN3. GCN4(Polaris) enhanced support but its still 1:1. Pre-GCN3 doesn't have any support meaning it has to be emulated. GCN5 brings 2:1

https://www.anandtech.com/show/8460/amd-radeon-r9-285-review/2

 

[AshlayW]

It's not all GCN GPUs. First support with GCN3. GCN4(Polaris) enhanced support but its still 1:1. Pre-GCN3 doesn't have any support meaning it has to be emulated. GCN5 brings 2:1

https://www.anandtech.com/show/8460/amd-radeon-r9-285-review/2

Thanks! So Hawaii is what effective rate?

 

[IntelUser2000]

Thanks! So Hawaii is what effective rate?

If its emulating it'll be really slow. Hardware doesn't exist so it'll have to run it on software. Like maybe 10-30x the difference.

 

[DrMrLordX]

If its emulating it'll be really slow. Hardware doesn't exist so it'll have to run it on software. Like maybe 10-30x the difference.

That's quite strange. You would think that, at that point, you'd be better off just rewriting the code to use FP32 with values that would fit into 16-bit floats. Unless the higher precision would screw up the results?