CPU issues with all 4 cores enabled

[TonyBurn]

Hi, I really hope that someone can help me with a long standing problem I have had with my hackintosh install. I currently have a quad core QX6800 CPU in my computer, however always have problems with it when running with 4 cores. Whilst using either SL 10.6.3/7/8 or Lion, utilising 4 cores my compuer will often slow to respond and would often crash. When I set cpus=2 in the start up options, it will run perfectly.

The easiest way to demonstrate the fault is to play a flash video. When utilising all 4 cores, the video (not audio) will drop frames and stutter regardless of whether hardware acceleration is enabled or disabled, a few hours of prime95 will also kill the computer. However, when running with cpus=2, flash is perfect, games will run and prime95 will just keep on number crunching.

After lots of time and investigation I have come to the conclusion that it must be something to do with the speed/fsb of my cpu or detection of cpu for OS X. I have managed to play flash video perfectly after a vanilla install of 10.6.3 and booting in safe mode.

However, once I install the 10.6.8 combo update and multibeast with the dsdt for my G41M-Combo and reboot with 4 cores enabled, flash video is once again buggy. Booting with cpus=2, it'll run perfect (albeit only on 2 cores)

I've tried setting detect C and P states in smbios.plist athough I am not sure if this applies to my CPU. I've also tried enabling and disabling various power saving and speedstep features in the BIOS.

So, is there a tool I can use that better identify the cause of the issue in OS X other than me simply opening youtube? And who could advise as to what the issue could be and how I can resolve?

Any help is very much appreciated, I've been using a crippled OS X install for far too long.

 

[TonyBurn]

Hi, thanks for the quick reply. I have the latest BIOS installed, version F3 as listed here:

http://www.gigabyte.com/products/produc ... =3505#bios

I've also tried both the EasyDSDT and the UserDSDT options, the results are exactly the same for both. Yes, I have various backups, I also have the install process streamlined efficiently now

Are there any other things I can try? I'm thinking the issue may be around a particular kext that is feeding wrong values of my CPU to the kernel maybe?

 

[TonyBurn]

**** Update with details of resolution ****

Finally I resolved this issue last night. I was reaching the end of my tether and weighing up alternative OS's when something in the kernel log, "unsynchronized tsc" caught my eye.

Upon a bit of googling I'd found that many other people where experiencing the same problem as me on a wide range of CPU's, anything from dual core to i7.

To rectify the issue I installed the VoodooTSCSync.kext as recommended on the following guide:..

viewtopic.php?f=34&t=3361&start=10

First boot and I had a kernel panic, second boot it worked fine. My boot can sometimes stall if I don't use the '-v' option. I think it may be to do with the timing of the kext being loaded? Whatever that problem, its not really a problem, I have no issues with that, and more importantly I can use all 4 cores for processor intensive tasks such as flash videos and VM testing.

Thanks for those who contributed to this thread. Hope the information I have posted here is of use to anyone else. Can a moderator please mark this thread as resolved?