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[Raistmer]

reported freq never reached in computations...

Before upgrade to Catalyst 11.2 CLInfo reported 750MHz as Max GPU frequency and that was correct cause when GPU has work it operates on 750MHz and drops its freq to 500MHz when idle (HD4870).

But now, after update to Catalyst 11.2, CLInfo reports 790MHz as GPU max frequency. 790 is max value that can be set in Catalyst overdrive, it's never reached by GPU itself, it requires that user deliberately move Overdrive slider to that value.
That is, this reported 790MHz does not reflect actual GPU performance (that still operates on 750MHz or 500MHz when idle) in any way.

The question is: what rationale was behind this change in Catalyst 11.2
Why OpenCL applications are decived now with artifically high GPU clock frequency reported to them ???

[Raistmer]

Any thoughts?
This 790MHz means absolutely nothing for my GPU cause its operational freq is 750MHz, not 790MHz. And 790 is highest one only for Catalyst Overdrive, I can set it higher with third party tools, so this value is just USELESS. For what reason it now reported in CLinfo? To decive application maker in card productivity?

[himanshu_gautam]

raistmer,

I checked that out for my juniper. CLInfo shows 850 MHz(expected) if i set the core frequency to any value less than equal to 850 using CCC. But when i set core frequency by enabling overclocked mode and set frequency to 960 MHz clInfo also returns 960 MHz. Shouldn't this be apt? Or are you doing something different?

[Raistmer]

So you proved that this is HD4xxx specific perhaps [not only HD4 but HD6 too, see next post]
When freq setted on 750MHz in Catalyst Overdrive, CLInfo returns 790MHz for my HD4870. Catalyst 11.2
Before upgrade I used Catalyst 10.12 and under this driver version the same CLInfo showed 750MHz as it should be.

[Raistmer]

Ok, and here is report from HD6970 card owner, same issue:


Max clock frequency: 950Mhz (In Catalyst Control Center it is set 880Mhz)!
Name: Cayman
Vendor: Advanced Micro Devices, Inc.
Driver version: CAL 1.4.1016
Version: OpenCL 1.1 ATI-Stream-v2.3 (451)

[MicahVillmow]

Himanshu,
This is an issue with the NI class devices only, the EG classes don't have the dynamic power management.

[MicahVillmow]

Raistmer,
Is this being reported on windows, linux, or both?

[MicahVillmow]

Raistmer,
I've been told that this has already been fixed in the next catalyst release.

[Raistmer]

Originally posted by: MicahVillmow

Raistmer,

I've been told that this has already been fixed in the next catalyst release.

Fine! Thanks for info.
And for record: it was on windows, don't know about linux case.