PowerPC G5 Wont Boot After Installing latest Security Patch

Can anyone help with this?

I was running 10.4.11

Downloaded and installed the latest security update for May.

When I turn on the PC it shows the Grey Apple on the white screen and the circle is ticking below. After a few minutes the PC completely shuts/powers down...

If I hold the power button down, it will allow me to get to a screen where it tells me to type "mac-boot" and then I can get in. Is this the equivalent of safe mode to a windows pc?

Once i was in, I tried to do the "Repair Permissions" from the disk utility but it didn't work. I also tried to unplug the power cord for 20-30 seconds and plug it back it and try to start up (this is supposed to reset something internally i guess?) No luck with those two

I did run a scan for hardware problems and it came up with something about the fan or the fan speed but I don't think that is the issue here.

This from an earlier post (yesterday) of the same problem (credit to Colin Bl)....
"If you hold down the shift key once you hear the chime it might boot up in Safe Mode.
Safe Mode;
Checks your Hard drive
Brings up Login screen
Turns off kernel extensions
Turns off fonts
Trashes font cache
Turns off login items
so in a way it is a level of troubleshooting. If you get back in I would download the Combo updater from apple site and run that - often that is enough to get things back to normal."

?

What is a combo updater? Would it be possible to link me? Thanks in advance

Sorry for a being a noob

THe combo update can be downloaded from this link




Apple - Downloads - Mac OS X Updates - Mac OS X 10.4.11 Combo Update (PPC)

No luck with the Combo Update

OK so I went ahead and installed the Combo update and it is Still Not Working !

Can anyone help with these please??

It still gets to the White Screen with the Gray Apple Logo and then just shuts down after a few seconds.

I can only get in by typing "Mac-boot" at a certain screen that only comes up if I hold the power button for 10-15 seconds

See if this is of any use to your situation Reset button PowerPC G5 - Google Search.

Will try

I did try to unplug the power cord for 2 minutes then plug it back in. I will look tomorrow to see if there is a SMU switch inside to reset, but i don't believe it is on the model that I have.