[quicksilverG4]

Just picked up a MDD dual 867 that the previous owner says wouldn't boot. Figured the problem was a damaged hard drive or OS install but it appears to be the ATA-100 bus. Swapped in a spare drive with 10.3 installed and it booted fine off the ATA-66 and ATA-33 busses but not off the ATA-100.

The ATA-100 connector is located just below the heatsink, has anyone heard of heat related problems with this part?

I don't have the original CD's so if there was a diagnostics CD for this model I haven't got it. Is there anything else I can do to confirm that its really dead? I guess I could boot off one of the other busses with a drive attached to the ATA-100 and see if Apple Sys Profiler picks up the ATA-100 drive.

Any chance there's something I can do that might revive this other than a logicboard replacement? I know I can stick in an ATA-133 card and run off that but it still irks me to have part of my Mac broken!

And I don't know if the seller knew this was the real problem or he received the Mac non-working, but someone's been mucking around inside because the drive cables were moved all over the place. How should the CD-ROM cable be routed? It was crammed between the drive cage and the heatsink when I got the Mac.

thanks

QSG4
---------
Apple Powermac "Quicksilver" 733 G4 - OS X - FOR SALE!!!
SGI Octane2 360 R12K - IRIX 6.5
Athlon64 PC - Windows 2000

[OreoCookie]

Get an ATA133 card. If you are sure it's only that part of the system which is shot, it should solve your problems.

[dave49er]

Have you tried changing the cable itself?

[quicksilverG4]

I got it working! For some reason putting my test hard drive on Master instead of cable select allows it to boot off the ATA-100.

Now to look into bumping it up to 167MHz from 133

[angelmb]

Originally Posted by quicksilverG4

I got it working! For some reason putting my test hard drive on Master instead of cable select allows it to boot off the ATA-100.

Now to look into bumping it up to 167MHz from 133

I would like to know the difference between master/slave and cable select since my MDD has two internal hard disk working fine as master/slave and I have read cable select is recommended for this particular Power Mac.

[P]

The IDE specification requires that one drive on the chain is master and the other is slave. Using Cable Select means that the driver expects the IDE controller chip to order each drive around, telling it to be Master or Slave. If you set it to either master or slave explicitly on the drive, the orders from the IDE controller are ignored.

If everything in the chain is according to spec, it shouldn't really matter as long as all the dirves in the chain have either CS on or CS off. Bad controller chips can sometimes be confused by the drives ignoring its commands, in which case CS is recommended. However there are also situations where the drives work better when set to master/slave, as that is the original setup - especially if the cable is an old one before this addition to the standard. IMO, cable select should be avoided - it's a late addition to the standard that requires a special controller chip, compatible drives and a compatible cable. If the computer doesn't accept your setup, flip the master and the slave and it usually works.

[angelmb]

Thank you very much P