AMD Catalyst 11.7 Preview + OpenCL 2.5.684.211

[niooron]

This driver lowered my mhash from 180 to 177 on my 5750 and from 117 to 115 on my 6570.
Sticking to 2.4 for now.

[hennessy]

I did test this driver release on Win7, and the CPU bug bit again - 100% CPU on one CPU core while running phoenix phatk. Going back to 11.6, and the CPU usage is back to 1%.

unless you're using only one GPU, I don't see how this could be true.

[Meatball]

Tested it with two different cards, a 6950 and a 5830, and got no change (6950, Cat 11.6, SDK 2.4 -> Cat 11.7, SDK 2.5) to a decrease in speed of ~ 10% (5830, Cat 11.5, SDK 2.1 -> Cat 11.7 SDK 2.5).

Using Windows 7 on both machines, GUIMiner with Poclbm.

[deepceleron]

I did test this driver release on Win7, and the CPU bug bit again - 100% CPU on one CPU core while running phoenix phatk. Going back to 11.6, and the CPU usage is back to 1%.

unless you're using only one GPU, I don't see how this could be true.

One CPU's usage is pegged at 100%? And yes, that Win7 machine only has one 5830.

[sirky]

I did test this driver release on Win7, and the CPU bug bit again - 100% CPU on one CPU core while running phoenix phatk. Going back to 11.6, and the CPU usage is back to 1%.

unless you're using only one GPU, I don't see how this could be true.

One CPU's usage is pegged at 100%? And yes, that Win7 machine only has one 5830.

I also have 11.7, and am dealing with the 100% CPU bug.

[Coinbuck @ BTCLot]

I hate this CPU bug

[m0ep]

I switched to Ubuntu today because of the cpu bug - and now I'm happy (although I still have some other problems with Ubuntu - but miners are working without CPU load ) 

[DiabloD3]

I hate this CPU bug

It only effects Windows, and only some Windows users. Its similar to the SDK 2.2/2.3 bug and its caused by a broken busy loop that doesn't properly sleep.

[Bitcoin_Silver_Supply]

I hate this CPU bug

Second, it would be very nice to find some sort of fix but I get the sense there just isn't enough demand.

[Meatball]

Does anyone know if this 100% CPU bug is actually causing the CPU to truly run at 100% and drawing the extra power?  Even though I see the poclbm processes on my machines that have more than one card showing it's using 100% CPU, the systems are perfectly fine and responsive.  Usually on a system with a CPU 100% pegged it gets laggy, but this isn't the case with this 'bug'.

Now, if it is truly pulling all that extra power to drive the CPU at 100%, that can start adding up real quick...

[organofcorti]

Yep, cpu bug caused my sempron single core to max out and bsod from heat after 30 minutes.

[Meatball]

Damn, that sucks.  So basically I'm wasting a few hundred watts of power running CPU's across my rigs for no reason.  Hope they fix this

And yes, I know I can go to Linux and avoid this, but I'm much more comfortable with Windows and the GPU over/underclocking capabilities.

[OCedHrt]

Discovered a 2.5.684.212 SDK But numbers seem to be the same.

[Rebelstar]

Guys, I heard in this topic someone downcloked memory on 69XX. Still not sure how to downclock memory from 1375 to lower clocks on 6950@70 and on pure 6970
Tried to do this via MSIAF but it's still keeping constant 1375 clocks.
Same question for the overclock, trying to overclock my 6970 over than 950mhz via MSIAF and Power +20% immediately reset in CCC causing constant GPU mhz jumps from 900 to 980. How to hold Power +20% and OC more than 950?

P.S. No M/hash increase/change on my 2 6950@70 and single 6970 with 11.7 preview and sdk 2.4

915mhz - 393 m/hash
910mhz - 385 m/hash
950mhz - 410 m/hash

[OCedHrt]

Guys, I heard in this topic someone downcloked memory on 69XX. Still not sure how to downclock memory from 1375 to lower clocks on 6950@70 and on pure 6970
Tried to do this via MSIAF but it's still keeping constant 1375 clocks.
Same question for the overclock, trying to overclock my 6970 over than 950mhz via MSIAF and Power +20% immediately reset in CCC causing constant GPU mhz jumps from 900 to 980. How to hold Power +20% and OC more than 950?

P.S. No M/hash increase/change on my 2 6950@70 and single 6970 with 11.7 preview and sdk 2.4

915mhz - 393 m/hash
910mhz - 385 m/hash
950mhz - 410 m/hash

I had same problem as you on my 6870 but was able to downclock memory using clocktweak. However, there is no performance gain. If anything, it might be slightly slower.

[Meatball]

Yeah, toss out CCC if you want to do any serious over/underclocking and go with something like MSI Afterburner and Trixx.

As for underclocking your memory, you won't see any performance boost.  What you will see is likely lower power draw and heat off the card.  That will sometimes free up a bit of headroom for you to give the core clock a bit more Mhz and boost your performance.

I've been running a 6950 (with the unlocked shaders Bios) at 880/625 without a problem and pulling around 390 MH/s.

[Rebelstar]

Thank you for answers guys.
Okay, as I understand I can lower my memory clock to 625 only at default GPU speeds (880) and with uninstalled CCC? And if I'll overclock GPU more than 880 I'll receive constant jumping GPU speeds like 880/910/880/910/880 because of "Power +20%" increase lack, right? As I know I can control "Power" limiter only from CCC.