How to get ATI Radeon HD 68xx to not drop performance after sleep (10.7.5)

[mazenmardini]

How to get ATI Radeon HD 68xx not to drop performance after sleep (10.7.5)

Hello, here is just a little tip for those with ATI Radeon HD 68xx cards.

Someone here at the forums earlier when 10.7.5 was release posted an issue with sleep/wake, you can read it here: http://www.tonymacx86.com/articles/72947-article-mac-os-x-10-7-5-update.html#post453170

The issue is basically that performance drops dramatically after wake. For me it went down to a whole 60% performance decrease!

The good news is that this can be solved by changing System Definition. If you're using Mac Pro 3,1, this bug will haunt you every time you sleep/wake I'm afraid. Instead you better use iMac 11,2. Why 11,2 is because that's what I found most suitable when it comes to compatibility/performance. iMac 11,2 in my case is very close to Mac Pro 3,1 in performance and it eliminated this wake issue.

Good luck!

 

[SubXero]

Hello, here is just a little tip for those with ATI Radeon HD 68xx cards.

Someone here at the forums earlier when 10.7.5 was release posted an issue with sleep/wake, you can read it here: http://www.tonymacx86.com/articles/72947-article-mac-os-x-10-7-5-update.html#post453170

The issue is basically that performance drops dramatically after wake. For me it went down to a whole 60% performance decrease!

The good news is that this can be solved by changing System Definition. If you're using Mac Pro 3,1, this bug will haunt you every time you sleep/wake I'm afraid. Instead you better use iMac 11,2. Why 11,2 is because that's what I found most suitable when it comes to compatibility/performance. iMac 11,2 in my case is very close to Mac Pro 3,1 in performance and it eliminated this wake issue.

Good luck!

It's not a bug with the 3,1 MacPro SMBios. It's just that AppleGraphicsPowerManagement.kext (AGPM) , which is responsible for graphics performance control, does not load using the 3,1 SMBios. It is not meant to. 3,1 is for older MacPro's with older GPU's that don't need power management. Most new desktops with the latest GPU's should ideally be on 5,1 to 12,2 depending on hardware specs. Anything from 4,1 up to 12,2 will load AGPM. 3,1 is included as a default in most installers since it gives the least problems and allows you to make the required edits to AGPM etc. to move on to the correct SMBios. You can further enhance performance by editing threshold values in AGPM to optimize your specific model of GPU, but that is a whole new topic.

 

[mazenmardini]

It's not a bug with the 3,1 MacPro SMBios. It's just that AppleGraphicsPowerManagement.kext (AGPM) , which is responsible for graphics performance control, does not load using the 3,1 SMBios. It is not meant to. 3,1 is for older MacPro's with older GPU's that don't need power management. Most new desktops with the latest GPU's should ideally be on 5,1 to 12,2 depending on hardware specs. Anything from 4,1 up to 12,2 will load AGPM. 3,1 is included as a default in most installers since it gives the least problems and allows you to make the required edits to AGPM etc. to move on to the correct SMBios. You can further enhance performance by editing threshold values in AGPM to optimize your specific model of GPU, but that is a whole new topic.

Very interesting, thanks for clarifying what the root problem was. Editing AGPM for higher performance you say? hmm, I don't want to take the risk of burning my card so I guess I'll keep the defaults. xD

I thought about something before, if it's possible to fool certain kexts into believing you're a Mac Pro 3,1 or a iMac 12,2 or whatever to gain the best features from each system definition. Is that even possible?

P.S. Mac Pro 4,1 gave me KP and removing AppleTyMCEDriver.kext wouldn't solve the problem.

 

[SubXero]

Why even try 4,1? You have a LGA1155 board & processor. The best match for that is one of the i-mac profiles 12,1 or 12,2. In fact, the AGPM in those profiles would best suit your graphics card anyway. I use a 6850 and the AGPM values in the .plist support my card natively using the 12,2 profile. The Vendor & device id are there by default. You would also not have to delete any kexts or get any kernel panics. MacPro 4,1 & 5,1 are for Socket775 boards - (Core2Duo).

It's not a big deal really, just pointing out facts from a purist point of view. A lot of guys are running on the wrong profile without much hassle, but are oblivious of the positive impact the correct SMBios can produce.

 

[mazenmardini]

Why even try 4,1? You have a LGA1155 board & processor. The best match for that is one of the i-mac profiles 12,1 or 12,2. In fact, the AGPM in those profiles would best suit your graphics card anyway. I use a 6850 and the AGPM values in the .plist support my card natively using the 12,2 profile. The Vendor & device id are there by default. You would also not have to delete any kexts or get any kernel panics. MacPro 4,1 & 5,1 are for Socket775 boards - (Core2Duo).

It's not a big deal really, just pointing out facts from a purist point of view. A lot of guys are running on the wrong profile without much hassle, but are oblivious of the positive impact the correct SMBios can produce.

I went for iMac 11,2 and it's performing a little better than 12,1 and 12,2.

The reason to why I tried Mac Pro is because it has better audio quality than iMac. I had issues with AGPM on the standard Mac Pro 3,1 so I went for newer versions, that's why I was trying out Mac Pro 4,1. Obviously that didn't work out very well, so I soon found another solution which was replacing AppleHDA with a modified version of VoodooHDA and then switch to iMac 11,2 to get the best out of my graphics card. So now I have both great audio and great graphics performence.

Btw, the modified version of VoodooHDA is: http://www.tonymacx86.com/audio/46043-modified-voodoohda-2-7-3-no-noise-pops-192khz-sample-rate.html