[e151280]

Hello all,
I'm totally new to MAC computers, been deeply involved with x86 architecture pcs & servers for over 24yrs. Opportunity presented itself today for me to possibly own a used PowerMAC G4 if i can get it working. Since I have always WANTED a mac, but couldn't justify the cost, I got very excited about the idea. It has no ram or hard disk. It has an AGP video card. I opened the unit & was pleased to see familiar (PC) 64bit pci slots & sdram memory slots.

I dropped in a known-working 40GB parallel ATA drive & a 512MB-PC133 sdram chip & plugged the unit up, but no display/no audible clues (p.o.s.t. beeps), just a lot of HOT air blowing out of the back of the unit.

Anyone have any comments on wether this unit is worth the cost of repairing? Bear in mind that I have NO operating system to load (I was thinking about Yellow Dog Linux for starters). I think the pc shop would probably want about $80.00 for the unit as-is, and the rest would be on me to repair.

The unit has a 500mhz / 1mb cache processor. Not a speed demon, but I just want to learn something about the Mac.

[cgc]

What would YDL teach you about a Mac?

The PATA HDD needs to be formatted to work and I'd check the seating of the video card.

[mduell]

First, it's Mac not MAC.

[e151280]

ok.... me again.

I apologize for the error in capitalization. Perhaps from dealing with networking situations for so long, I inadvertently used the acronym MAC, as in Media Access Controller (network card). ALSO, the idea of using Yellow Dog Linux, was to get familiar with the hardware differences of the Mac vs x86 pc architecture, until I save up enough money to buy a copy of Apple's OS 9 or X.

All that aside, what I'm asking is:

"Is there anyone here that can advise me on the technical merits of attempting to get this computer working?"

"Is this unit worth putting the time, effort, and monetary expense into, to learn about a different type of computer than the ones I've worked on, and earned a living from?"

At the risk of starting some silly flaming, snide remarks, and spelling corrections aren't telling me much about Power Mac computers, and I wrote in expressing a genuine interest.

[hookem2oo7]

Well, putting linux on a Mac will be nearly identical in terms of user experience to putting linux on a PC. Sure, there are hardware differences, but in broad terms, linux is linux no matter what it's running on. IMO, to get the full "Mac experience" you should throw a copy of OS 9 or OS X on there.

As far as getting it running...have you tried a different stick of RAM? Some high-density 512 modules have caused me similar no-boot problems in my experiences with G4s.

[reader50]

Your question is a bit hard to answer, it depends on what is wrong with the PowerMac. If the motherboard or (to a lesser extent) the power supply or CPU were blown, then it probably would not be worth it for you to fix it. Anything else is fair game.

Yours is one of the earlier PowerMac G4s, which should work with PC133 and PATA hard drives. It will be affected by the ATA 128/137 GB limit on drive sizes.

The unit may want PC100, and will reject PC133 if it's missing the SPD settings for operation at 100 speed - cheap RAM sticks sometimes omit the slower settings even though they are perfectly capable of working at 100 MHz. We think the manufacturer doesn't want to spend the extra pennies doing the test, when so few systems need 100 MHz today.

note: These PowerMacs are picky about 512 modules. At the time they were designed, 512 modules existed only as engineering samples. The column/row maximums that Apple settled on for the controller turned out to be different from the popular ones used a few years later when everyone caught up. Common PC 512 modules usually don't work - they either recognize as 256MB modules, or they don't work at all. This problem is almost entirely limited to 512 modules.

So you press the power button and the power supply starts up, but there is no startup tone. You should get a startup tone during the POST sequence. Proceeding from that info:

1. The power button may flash a diagnostic code indicating the reason for POST failure. The flash sequence will repeat. Let us know how many flashes in the sequence.
... 2 flashes: no RAM installed or detected
... 3 flashes: incompatible RAM types installed
... 4 flashes: no RAM banks passed testing
... 5 flashes: bad boot ROM (failed checksum)

2. The motherboard likely needs a reset, especially if there is no flash code on the power button. The reset switch is located near the rear of the motherboard, next to the PRAM battery. With the system powered down, press and hold this button for up to 10 seconds. Then try to power up again.


3. The battery is likely dead anyway, which may make the system unable to boot. You can get a replacement from Radio Shack #23-026 for about $10.


If you do replace the battery, do the steps in reverse order. ie - install new battery. A few minutes later, press and hold the reset button for up to 10 seconds. Then try to boot, and read the flash codes if it doesn't make it past POST.

With no OS image to boot from, boot will fail. But you should get an image on the screen with an error icon - usually a blinking folder icon indicating no usable system folder found. You should also get a startup tone.

[goMac]

Originally Posted by hookem2oo7 

Well, putting linux on a Mac will be nearly identical in terms of user experience to putting linux on a PC. Sure, there are hardware differences, but in broad terms, linux is linux no matter what it's running on. IMO, to get the full "Mac experience" you should throw a copy of OS 9 or OS X on there.

Mac OS 9 is hardly the Mac experience these days. I'd say go for OS X instead of OS 9.

[P]

While you have the box open, look for any leaking or bulging caps. Unfortunately common on computers from a certain time period, especially from Apple and Dell.

That battery can also be found in photo shops - it's used for flashes in certain cameras - if you can't find it anywhere else. It's 3.6V lithium battery.

Ditto on dense RAM chips, by the way - that's a likely cause. You can read out the statistics on a RAM circuit in a (known working) PC to see if it has timings defined for PC100 mode.

I would recommend you not to spend anything on the Powermac - except for possibly that battery. A new Mac mini is $599 for a much more capable machine with the latest version of OS X included. There are refurbs at much less, and used models as well. You don't really notice PPC vs. x86 unless you're doing rather low-level programming - what's unique about the Mac is the operating system.