I've tried just about everything mentioned on this thread with no success. Once my CPU undergoes significant load, the various problems start surfacing.

But for now, I can live with using one core. I can manage to play 720p with Mplayer OSX 1.0 RC2 with only minor instances of lagging. The lag was a concern for me using a single core but I realized I wasn't using the RC2 version of the player.

I just added the cpus=1 flag to my boot.plist, it's time for me as well...
The only application that seems to be able to cause the mouse movement bug is Photoshop CS3.

I use it a lot at the moment. Rebooting now.

I never had problems, like strange mouse movements, mouse jumpung or things like that. But what i noticed after installing OS-X onto 2 AMD machines, one Intel C2D desktop and Intel C2D laptop machine is that somehow on my amd machine mouse movements are somehow very unnatural comparing to windows or linux. Its very annoying. On intel machines its just great but only on AMD machine very unnatural and really not comfort using mouse as in windows. I tested with 3 different mice, the same. I am used to this almost, after 5-6 months, but what i wanted to say is this kind of movement i really didnt notice on my other Intel machine.

The more AMD users recognise this is problem the quicker we can find a solution. I know Jas might be looking into it, I wonder if the great Zephyroth has any input/suggestions?

To summarise this for future reference; it is not a 'mouse bug' per se, but a dual core timing issue.
Symptoms include:
• Mouse lag - early signs are drag and drop inaccuracies, trail skipping
• GUI lag - Finder window movement becomes choppy and acceleration degrades
• Random restarts - caused by the 'divide by zero' error resulting in kernel panic
• -10810 error - applications will not start until a restart or log out/in
• increased CPU fan noise and temperatures - due to dual core synchronisation errors
• general erratic behaviour - system feels sluggish, unresponsive at times

Remedy (Temporary)
• Boot using the 'cpus=1' kernel flag - this can be done at the beginning of each boot at the Darwin boot prompt, or permanently by editing the com.apple.boot.plist which can be found in: /Library/Preferences/SystemConfiguration/

I would like to ask, this happened in all versions of leopard?

Does it happens on tiger?

Is there any kernel that detects the 2 cores (in system profiler).

I do think it could have something to do with the HTT issue that happened in tiger.

:P

It also must be a problem depending on the hardware. My Dual Core Opteron 185 (2 x 2.86 GHz overclocked) works absolutely perfect. Firefox quits sometimes, but otherwise I have no problems. I'm running Leo4All V3 + 10.5.3 update by ASU. The board is nForce 4 SLI, Socket 939 with 4 GB DDR RAM 200 Mhz. Puttabongs Dual Core machine also runs fine as far as I know.

Maybe it's a software problem, especially Photoshop? I'm using Logic and have no problems. Or the gfx card? I presume you all have nVidia, I have an ATI.

Read a few posts back, Puttabong's hack recently became susceptible to the problem. This issue has been around (according to JaS) since the Tiger days, and it is not hardware related it is a timing issue at software level. You're just one of the lucky ones.

Yeah i am one of those lucky people too cause i don't have problems with this

and have a AMD Athlon 64 x2 5000+ and not one problem at all

To the people who say they have no problems, how long on average do you leave your hack on without rebooting.

Many of these issues don't appear until long period of uptime has passed. Also if any apps quit on you during this time with a divide by zero error then you are suffering from the dual core timing issue, albit mildly.