re: Mac OS crashing HELP PLS!

What do you mean by saying "within 5 min of startup"?
Also, it is hard to see what the problem is since you don't tell us what were you doing last time you opened your computer.

You don't tell us what do you mean by "computer crashed half way through". You mean you had a kernel panic, the application closed and the mouse and anything else was frozen? What was it?

You don't even tell us what your system is and what hardware you are using! How do you expect to get a decent answer?

Some things to do:
--Zap your PRAM.
--Startup from your OS X install CD, run disk utility and verify your disk.
--Perform the Apple Hardware Test that came with your computer
--Please give information about your current software and hardware, and tell more about the symptoms of your problems.

 

Where did you get your RAM from? Did you install it yourself, and if so, how long ago?

 

i would say you have a hardware difficulty, especially if you can't open the disk drive with the mouse click. Try taking out all the thirdparty RAM and leaving in the original apple ram, see if that works

 

G5 freezes

I hope this helps, I own a dual 2 GHz G5 and it randomly crashes regardless of OS version (I run tiger now) or application. The machine freezes and a red light comes on and the fans crank up.

(i) the red light (LED), (I believe there are two of them). The G5 has a clever cooling system and control electronics - varying the speeds of the nine fans etc to keep the computer temp within specs, however this system is independant of of the computer processors etc its a stand alone electronic circuit that does its own thing, a failsafe. And one of its requirements is that it gets an (everything is OK) signal from the computer/OS itself at least every 2 sec.
If not..it assumes the worst and its fans on full power and red light on to indicate a problem. The fans and red light are not the problem just an by product.

Its the computer OS thats freezing, I have read that certain video cards are causing the problems, some are more susceptible than others, I read about an developer who wrote a few lines of simple programming code that uses a few of the Open GL routines to do a screen draw and his routine can freeze his G5 pretty much 90% of the time.
Solutions there may be a firmware fix on the way either from Apple or the video card manufacturers. I may be completely wrong and I'm open to comments but this is where my research has led me so far. i have tried everything to remedy the problem on my own machine.

 

update

The OS does the monitoring of the internal machine temps and power requirements and passes this info on to the external circuitary,but its still the external circuitary that controls the fans and it does its failsafe thing (fans on full red light on)if communications with the OS fail for more than 2 mins.