Q: iMac G4 Kernel Panic

If there is a problem with the ATA/IDE HDD, you should seek

a new replacement, instead of breaking down another iMac G4

since then you'd have two apart and complicate the situation.

The information so far indicated a possible hardware issue behind

the kernel panic, to include RAM, clock battery, perhaps logic board

and before that, the original hard disk drive.

However there is no application of thermal paste on the plate you

describe. It goes on the thermal conduit that carries heat away

from the PPC CPU so the air-stream of the cooling fan dissipates

it from the chassis. So the old thermal paste on the processor where

the heat needs to be carried from, would be cleaned off both sides

of this, and new thermal paste carefully/evenly applied to both.

This, before you close the inner section of the computer, and prior

to attaching the bottom section, well before the bottom plate cover.

The iFixit instruction for these iMac G4 models is lacking in detail.

And there are differences in build models of iMac G4, so the other

instructions online (single image, not video) can be inaccurate. Yet

even a site such as XLR8 takepart for RAM and HD replacement

is better overall. So was Mr Totes page for later iMac G4 than yours.

•MrTotes - iMac G4 (flat panel)

http://www.mrtotes.co.uk/page1/page1.html

•iMac G4 Take-apart for Drive and RAM upgrade:

http://www.xlr8yourmac.com/systems/imac_g4/imacg4_takeapart.html

Somewhere I have a service manual, however for later 1.25GHz model

that I was given on .PDF (electronic copy) from when I had to further

troubleshoot mine, under AppleCare, to get the nearest (100+mi. away)

authorized service to attempt to fix it correctly. I didn't open mine up but

did not refuse the copy. These are very helpful, but hard to get. And a

manual for the older 'flat panel' 700/800 early series does exist. If you

do persist in repairing those, you may find access to that info online.

Hopefully you can sort out the issue without necessarily re-installing

the system software; an externally enclosed HDD (self-powered)

FireWire400 setup sporting the necessary 'oxford-type chip' helps.

Then you could install a full system there from the working iMac G4

and use that to troubleshoot (bootable) instead of taking the 700 apart.

I only have three (1.25GHz) iMac G4s. Anymore other than the display

I tend to prefer my G4 Mini 1.5GHz though it runs less RAM total.

Good luck!

The hard drive indicated in your link above won't work to boot a PowerPC

Mac computer, and the external should have a power supply so it won't rely

on the computer (should be running before computer is started up.) To get

and use a FireWire external enclosure if you want to have a bootable system

clone on an external drive, that can't be a USB ported enclosure.

And it can't be running off USB/FW port power. FW400 is suited for use with

many pre-2006 PPC Macs, and enclosures with oxford-type chipsets work.

The model listed below is in a durable case, has its own power supply, has

the oxford chipset, and can run a computer from a cloned OS X. (And it also

has USB2.0 ports, but they won't boot a PPC Mac; OK for storage access.)

The others likely will not. Here is an example of enclosure set to go w/HDD:

http://eshop.macsales.com/item/OWC/MAU4S7500G16/

Similar examples with & w/o HD drives (ports FW/USB) installed:

http://eshop.macsales.com/search/Elite+Pro+Oxford+934

The silver thermal paste such as OWC has seems to work on both desktop

and portable computers adequately, it is better than they'd used when new.

You may be able to get a download of vintage Carbon Copy Cloner

for use in OS X 10.4 or 10.3 systems, so as to copy/clone the system

off your computer if you wanted to keep it (not erase/reinstall) for use

in another replacement hard disk drive. Check the sites for CCC at

bombich.com, or SuperDuper at shirtpocket site, for older versions.

These run free, so are handy to have; especially if you have a boot

clone and wish to re-install the entire thing into a computer. Most

other utilities run from OSX clone on external self-powered FW HDD.

The 3.6v 1/2AA Lithium battery used in various Apple desktop models

can be called a PRAM battery, as it powers a chip that keeps settings

correct until it goes dead, and it does not get re-charged by the Mac.

It also powers the system clock that keeps the system + all files in order.

OWC has these for about $4. or so. You can always pay too much. I used

to buy these in bulk, for about 50¢ each, when restoring older PowerMacs.

Be sure to read up on the issues of using an SSD, since these desktop Macs

take the 3.5" larger size and for the cost, a 7200RPM 500GB HDD is less.

The SSD may do OK if in an external enclosure, with FireWire. If you hope to

swap a HDD from an enclosure into the old ATA/IDE (PATA) Mac computer,

then you have to be sure to get an SSD that works in the PATA computer.

And also get an external enclosure that works with the SSD, or other HDD.

Some brands of SSD may include or provide an adapter for PATA & SATA.

Don't bet on it, ask if you contact a product specialist at the retailer.

I'd not overly complicate this. And to have/get an externally enclosed HDD

for backup and bootable system clone/copies of your Mac's OS X, can be

a different enclosure than you'd use if you get an SSD. I'd partition a larger

capacity 7200RPM 3.5" and use that for more than one purpose, backup in

one partition and perhaps room for the cloned OS X boot system on another.

The OWC site has two case sizes of SSD, the 2.5" Legacy for portables, &

the 3.5" Legacy for desktop models. An external enclosure should match;

given the other aspect is PATA vs SATA. A hard drive that will live in the

external enclosure, would be OK if both parts inside there were SATA.

Just you would not be able to swap SATA HD in there with w/ ATA  iMac.

The iMac uses the standard 3.5" ATA/IDE, and 7200RPM may be faster

than stock in an early 700/800MHz iMac. Seems to me they shipped w/

5400 RPM spin-rate, when new; so they may run warmer with faster HD.

Anyway, these are considerations and possible trade-offs; an SSD for use

inside an early iMac G4 model may be OK, but there are other aspects of

those which may be impractical to upgrade too much. The OS X limit in

the slower processor is Tiger 10.4.11. Or, you could run a custom linux or

unix based system. A few/free are out there, but they won't run Apple s/w.

Be sure to check out various options before you finalize a plan...

A situation with the identity of the hard disk drive, and the optical drive, as seen

by the logic circuitry in the iMac, may yield unhappy results when trying to swap

one kind of drive with another. The data transfer speeds of optical drive could be

lower than those of a hard disk drive, depending on the configuration.

The computer may see the optical drive as a master, but this is an ATA IDE (PATA)

or Parallel ATA setup; and not one using SATA or serial ATA. The optical drive is

usually set to be able to start the computer with the system DVD or CD.

Anyway, the hour here is late and my memory on this topic isn't helpful. I'd have

to re-search information such as everymac and some from mactracker, among

others to see what I may be missing.

However, you could see about using a FireWire externally enclosed hard drive

for the system as a FW400 should be fast enough for booting an OS X. Another

idea would be to get and ready an OWC Legacy SSD (for ATA/IDE) from mac

sales.com and ready it for use before installing it. These are in use for several

models of older non-SATA and can be an impressive improvement over anything

stock when booting the OS or using any applications. Enough to supplement the

lack of additional RAM since swap files and virtual memory effects are good.

Later iMac G4 models had 7200-RPM 3.5-inch ATA/IDE drives that may be hard

to replace nowadays; earlier 700/800MHz had 5400-RPM 3.5-inch hard drives.

So this alone could effect better performance; while the Legacy OWC SSD for

older portable and desktop computers (the unit is 2.5-inch, and thinner) is best.

The cost & effort to change the drive over to an SSD along with troubleshooting

the setup, should issue develop, could be a deal breaker for such a Mac model.

An SSD should run cooler in iMac G4 series. There are several standard parts

in these that tend to be unstable over time; so spares may be difficult to locate.

For a time, MCE brand offered replacement optical drives; OWC may have some.

They had one in stock for awhile; other models for slot-load are more common.

I'd try to keep the internal optical drive; unless you could locate and figure out how

to use to your advantage, an externally enclosed tray-loading FireWire superdrive

equivalent. This kind of FireWire drive has a controller chip (as does external drive

housing) that allows for Mac OS and OS X booting. Old chips were 'oxford-type'

and newer ones are different, macsales.com offers some enclosures to boot from

that would be used with Clones or technical troubleshooting, and so on.

Though I've probably missed your question in this reply, I've just stopped in late to

see what kind of ASC activity is going on. Local time is few minute after midnight.

I have a iMac G4 1.25GHz 17-inch model USB2.0 that kernel panics, it was included

with one that was working at the time, as parts. I also got the original box. A working

one of that transaction has needed superdrive replaced. Those used a Panasonic

version with special firmware; there were topics in some sites years ago about how to

try & flash the firmware to get a different model to work. The optical drives appeared

to fail, about when you'd upgrade the OS X. No firmware upgrades solved the issue.

Anyway, it's time to go offline...

Good luck in this matter!