[sheer]

Good evening, not posted for a long long time, but put that down to a lack of problems in the last few years in my Mac world.

However, this last week my 2nd gen Dual 2.0 G5 (PPC970FX v3.0) has decided to become a single processor box. CHUD/Activity Monitor/System Info and Logic all confirm this along with the expected drop in performance and increased fan action. As a precaution I've reset both the PMU and PRAM along with checking the firmware, but to no avail. Is there anything else worth checking as I clutch at straws or am I basically stuck in single processor land?

I'm guessing a repair isn't going to be cheap (and I can't afford it right now anyway) but would saving for a MacIntel box be my best bet? I only use the G5 for Logic, soft synths/fx and a hub for music hardware but you can never have too much power in that respect. Bit miffed to be honest as the G5 has never been abused (or overused) and quite honestly, considering the initial investment this shouldn't happen so soon IMO. In comparison I've an older AMD64 box I built for a third of the price which has been overclocked (and basically hammered) and it still takes everything you throw at it.

Thanks in advance

[Todd Madson]

If you don't have Chud tools installed already from Apple, do so and try to enable the second processor.

If it's grayed out it's probably that something is really, really wrong and your dealer will need to look at it.

If it's expensive, I wouldn't bother to repair it, just take that $ and put it into a mac pro.

But try chud tools first and see how that works for you. It installs a system preferences pane that allows
you to try several things.

[sheer]

CHUD is already installed (as detailed in my original post). According to CHUD there is no second processor to enable, nothing is greyed out, no red star star with x2 on it, just one processor and that's my lot.

[sheer]

OMG

So I start fiddling with the ram in an act of straw clutching (I've already run Rember which said the ram was OK). The 2x256 Nanya it shipped with I put on the outside, moving the 2x512 Crucial to the inside followed by the 2x512 Hynix, thus:

Nanya 256
Hynix 512
Crucial 512
Crucial 512
Hynix 512
Nanya 256

I now have two cpus again

If anyone can explain how this makes a difference I'm all ears.

[tooki]

Changing the RAM configuration has the side effect of completely resetting your NVRAM. I'd bet that if you returned your RAM back to the previous configuration, the problem would not return.

I know that the NVRAM has an obscure configuration option to disable extra processors (e.g. for software testing, or as a workaround for a bug). Perhaps it got corrupted and thought it was set to disable the CPU.

[sheer]

Well, funny you should say that, as I fired up the Mac last night and lo and behold, back to single cpu

Did a restart, reset PRAM, and it was back to dual cpu. Restarted again and booted off the Tiger disc for a repair/verify, then back in to OSX and still dual cpu.

So, something at boot level (NVRAM perhaps) is corrupted? Any way to check (and fix this)?

Another thought, could the mobo battery be on its way out?

[tooki]

It's possible, if the machine has spent a lot of time unplugged.

But try doing a "deep" reset:

Restart while holding command-option-O-F (that's the letter o, not a zero)

Then type:
reset-nvram [press enter]
reset-all [press enter]

and then:
continue [press enter]