Mac Forum / General / Hardware / December 2005

To start of with, some background:

I have a G4 mirror drive door 1.25GHz dual processor system.  Some time
ago, the fan on the video card started making noise; the bearings are
shot.  Not just noisy, but the fan itself wobbles and the noise is when
it hits the side of the shield.  After the system has warmed up, though,
the noise goes away.

Also, the system tends to lock up.  Sometimes just the graphics,
sometimes the whole machine.  I had attributed this to the accumulated
cruft through the various crashes and upgrades since OS X 10.1.  Also,
there's a problem where if the machine crashes, I have to restore
/private from backup, or the netinfo database doesn't work.

Today, the machine froze up.  No matter what system I booted (there
is one system, 10.4.2, on the main disk, and two partitions with 10.3.9
and 10.4 on another disk), it would boot to a blue screen with pointer
and go no further.  After a period of time, the screen blanks, and a
wiggle of the mouse brings it back.

I disconnected all the drives except one that had no OS on it, and did
an install of 10.4.1 on it.  Does the same thing.  Funny thing is, the
installer disk will get to usable graphics, but not any installed OS.
I did a power cycle, booted the install CD, and used Terminal to look
at the system log.  The last two entries are:
localhost kernel[0]: Graphics chip error! Restarted.

So, I'm assuming at this point that the problem is with the graphics
card.  (GeForce4 Ti 4600 according to System Profiler.)  I would like
to get recommendations for a replacement graphics card that I can go
down to the local Fry's and pick up, that would work in my system.

Thanks,
Steve