Why is the new 1TB WD hard drive, installed in my G5 iMac (PPC) not recognized or detected.

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Why is the new 1TB WD hard drive, installed in my G5 iMac (PPC) not recognized or detected.

I installed a WD 1TB hard drive in my iMac G5, non-isight PPC, replacing the 500GB Seagate drive that I installed 6 or 7 years ago.

The 1TB drive was not detected. I removed it and used a drive adapter, connected to my G4 iBook. It was detected there and I was able to successfuly initialize it.

After reinstalling the drive inthe iMac, it was detected (woo-hoo!) and I was able to begin installing Leopard. At some point, while I wasnt in the room, the iMac restarted without completeing the installation and had returned to the language selection window.

The drive is no longer detected in the iMac.

I reset the PMU and PRAM, with the same results.

Is it possible that the 1TB drive is too large for the iMac to handle. From what i've researched, it should work in that computer.

Any thoughts are much appreciated.

Randy

iMac, Mac OS X (10.5.8), PPC Non-iSight, Non-ALS

Posted on Jan 21, 2014 12:05 PM

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Answer 1

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rccharles

Level 6

12,957 points

Jan 22, 2014 11:24 AM in response to DesertSage

Sata drives run at different bus speeds. I've read where the g5 run at the lowest speed. You new hd may be running too fast. There may be a jumper setting to slow it down.

Robert

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Answer 2

DesertSage Author

Level 2

171 points

Jan 22, 2014 1:48 PM in response to rccharles

Thanks Robert,

I did read about that somewhere and saw that there was a jumper setting to slow down the drive. I compared the speed of my current drive with the new drive, but I was looking at RPMs, 7200, which they were both the same, so I dismissed it.

You are speaking of bus speeds, though. I must have misinterpreted that. I should try the jumper setting, if I can find that again.... and find a jumper!

I thought it may be my SATA cables but when I reinstall the old drive, it works fine.

Randy

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Answer 3

DesertSage Author

Level 2

171 points

Jan 22, 2014 3:46 PM in response to rccharles

Hello again Robert,

Looking further into this, what I know is that my new WD drive is a SATA 6 (6Gb/s). Jumping pins 5 and 6 will lower the speed to 3Gb/s. Hopefully the iMac can auto negotiate from there.

If the HD were a Sata 3, I would be able to adjust the speed down to 1.5Gb/s by jumping pins 5 and 6.

The WD support diagrams I am seeing look like the end of a IDE drive to me. Has me a little confused. I will keep working on this and let you know how it turns out.

Thanks again for your tip.

Randy

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Answer 4

rccharles

Level 6

12,957 points

Jan 23, 2014 11:05 AM in response to DesertSage

If you cannot lower the speed enough, you could consider an external enclosure.

I'd give OWC a call. 1-815-338-8685.

Good luck. Glad you understand the situation now. Thanks for the info.

Robert

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Answer 5

DesertSage Author

Level 2

171 points

Jan 23, 2014 9:20 PM in response to rccharles

Hi Robert,

I contacted Western digital. The best they could do for me is to have me jump pins 5 and 6. This will lower the speed to 3 Gb/s.

If that doesn't work, I guess the enclosure idea will have to. I currently have a LaCie firewire external backup drive that is bootable. I'm using it now and the lag time is a little disapointing.

I don't suppose there is a Mac disc utility that could deal with that speed differential? I'll have to search around.

Thanks again Robert,

Randy

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Answer 6

a brody

Level 10

82,941 points

Jan 26, 2014 10:19 AM in response to DesertSage

Many hard drives will work on slower bus speeds, but they need a jumper to set them up for a lower speed. Contact the hard drive manufacturer to find if that is possible.

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Answer 7

DesertSage Author

Level 2

171 points

Jan 29, 2014 8:09 PM in response to a brody

Thanks Brody,

Yes, I did contact Western Digital about this. They have been very communicative and helpful. Apparently, my only option is to jump pins 5 and 6, lowering the speed to 3Gb/s.

I just received my jumpers and am going to give it a go, hoping that the iMac can self negotiate the speed down to 1.5 Gb/s.

Randy

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Answer 8

DesertSage Author

Level 2

171 points

Feb 2, 2014 11:09 AM in response to rccharles

I just wanted to say thank you and that, yes, the jumper setting solved the issue.

I jumped pins 5 and 6 according to WD customer support instructions. This lowered the speed from 6Gb/s to 3Gb/s. Bus speed of the iMac G5 is 1.5Gb/s, but it was able to self negotiate from there.

The 6Gb/s was just too much for the old iMac.

Nice to have it up and running again with a new 1TB HD.

I'm so glad that I used Smart Utility. It gave me the early warning info that the old drive was failing, while Smart Reporter was still green.

Randy

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Answer 9

rccharles

Level 6

12,957 points

Feb 2, 2014 11:45 AM in response to DesertSage

Glad to hear. Happy computing.

Robert

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