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Apple iMAC Slim 2012 - Brightness Control Interference


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iMac 27" Late 2012 i5 3.2ghz 32gb RAM

Nvidia GTX 675MX 1GB Ram

Windows 8 Pro 64bit

BootCamp v4.1 Drivers (Current)

Aida64 2.80.2300



When both "Load Kernel Driver" and "Low-Level SMBus" options are selected, Aida64 will disable the brightness control and induces a freeze/lag when attempting to adjust the brightness via the keyboard function FX keys. While pressing FN+F1/F2 brightness down/up it causes the computer to freeze momentary, mouse and keyboard are frozen momentary and the brightness control no longer function leaving the brightness at the lowest level. The issue persists even if we close Aida64.


If any one of the two stability options are unchecked, everything works fine. (except detailed temps are not shown) The problem only occurs when both these options are used together.



To restore the brightness control functionality we need to close Aida64 and put the computer to sleep and then wake it up. Upon waking up the brightness control is restored, until we run Aida64 again with the above options ticked. Rebooting works also.


With the above in mind, we cannot have a fully functional Aida64 on the latest slim iMac's with the Ivy-Bridge.


Any suggestions?

(Machine Details are in the attached Aida64 Report)

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Thank you for the detailed bug report.  If it's possible, please manually submit a report to us (in AIDA64 / main menu / Report / Submit Report To FinalWire),  and in the report submit window make sure to have  all 3  debug dump options enabled (checked).  Also, it would be best if you could do the report submit while having the SMBus and kernel driver stability options enabled, and so the brightness control interface is "mixed up".  We need those, because it may be possible to filter out a single SMBus device address where the brightness control interface is found.  If  we could see the full SMBus dump, that  may give us an idea on where to find the brightness control interface.


Alternatively, you can make  a new AIDA64 report, a full SMBus Dump (right-click  on the bottom status bar of AIDA64 main window --> Sensor Debug --> SMBus Dump (Full) ), and an ISA Sensor Dump (right-click  on the bottom status bar of AIDA64 main window --> Sensor Debug --> ISA Sensor Dump), compress the files using ZIP, 7Zip or RAR, and attach it to your post in this forum.  Before attaching the compressed file, please rename it to attach.txt.




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