[phuture]

My G4's been in storage for about a year and yesterday I broke it out, set it up, and upgraded it to Tiger. I think one of my processors is now disabled! Here's the machine's specs:

dual 450mhz G4 processors
1.128 GB RAM
Seagate 7200rpm 120GB drive
airport
16X DVD DL burner
ATI Radeon video card 32MB (pulled from a Quiksilver G4)
Apple studio display 17" LCD

This computer used to run Jaguar and it did really well. And then I upgraded to Tiger last nite and performance went downhill (yes, I waited for Tiger's spotlight to finish indexing). Activity monitor only shows one CPU working while the other's window is completely black. Same thing with the Dashboard stats widget. CPU monitor in Jaguar used to show activity on both CPUs. I ripped a CD in iTunes -- max 5.8x versus Jaguar's sustained 12x speeds. So then I XBench'd it and it scored a pathetic 17.1!!! My fears confirmed!!!

I don't understand! Did tiger disable one of the processors? I know it disabled the temperature sensors on the processors. How can I get this machine's full performance back without reverting to Jaguar? Please help, thank you!!!

[reader50]

Did you confirm it was still running Jag stable, with both CPUs before beginning the upgrade? A year in storage is a long time. Boot into your old Jag partition, and see if both processors show there.

Is this a CPU upgrade card? And did Tiger require a firmware upgrade before it would install? If so, you may need to hit up your upgrade's site and get a custom firmware to let OSX recognize both CPUs again.

[Kenneth]

I would try CHUD Tools. It provides more information about the processor and other neat things.

[phuture]

The CPUs are both original and have never been removed or modified. It was running stable on Jaguar except for the "jag-lag" on startup inherent to OS 10.2. I noticed that both processors would be running on startup, it's just when the computer went to sleep then woke up that a processor would get disabled.

The strangest thing is that now the problem is totally gone, no tweaking or reinstalling the OS or anything! Both CPUs are firing even after waking from sleep! Perhaps it just needed to get "settled in" to Tiger? Thanks!

[ChrisF]

Originally Posted by phuture 

The strangest thing is that now the problem is totally gone, no tweaking or reinstalling the OS or anything! Both CPUs are firing even after waking from sleep! Perhaps it just needed to get "settled in" to Tiger? Thanks!

I have a dual 500 MHz G4 which has done this before. I don't use the machine very often but every now and then it starts up as a single CPU machine. A reboot generally solves it.