Is there a list of "APPROVED REPLACEMENT HDD" for the 21.5 late 2009 iMac that has the built in temperature sensor?

Well I went ahead and fitted a new ST3500413AS. And the machine feels faster than it did before. It seems possible that the "failing" status might have resulted in relatively poor performance? I doubt the small performance enhancments of the new drive would have made any real difference.

A few points:

Glass removal was really easy - I used a suction tool sold for carrying sheets of glass. Maybe a bit over the top but it made the removal so quick and secure it was worth getting - and I really didn't have anything else to use. No - not even a sink plunger.

The ifixit instructions did not actually match up with the details of this machine. The screen removal and display panel release was spot on - except the screws were Torx 10 when described as Torx 8 (or was that the other way around?).

Identified the four cables to be disconnected and undid the two on the right. But the main connector was very different to the one described so paused and thought. Then realised that it might be possible to remove the drive without going any further.

Undid the two Torx screws (10?) at the front of the drive mount, removed the three cables connected to the drive, and slid the carrier out. Left the display resting gently where it was. Removed the ironmongery from the side of the drive - and the two screwed in pins on the far side (Torx 8?). Attached them to the new drive and reversed the procedure.

At this point I wondered if I could have done the whole procedure without disconnecting the two display cables at the right - and, whilst I did not re-check, I think it just might be possible. But only if your Torx driver is relatively short - so that the display panel does not have to be lifted very high when undoing the hard drive mount screws.

Simple enough anyway to reconnect the two cables, re-screw the display, clean and refit the glass. And that was that.

Aside from solving the fan issue with software - alll worked fine. Including the extra 8 GB of RAM I also added. Mmmm - maybe shift up to 12 GB has helped with performance?

But the crazy thing is we now have a drive with a 3-year manufacturer warranty. And a screen removal tool. And three times the RAM. For a total of around GBP 100 including the fan software. If we had gone with an Apple repair we would only have had a repair warranty (90 days?), no extra RAM, no screen removal tool, no heart-stoppng experiences, no satisfaction - and we were quoted GBP 183 by an Apple authorised repairer.

Still very annoying that there seems to be no way of applying the Apple firmware to a new drive. The ability to do that would have been the icing.

Rod

thanks for the imput sir,

may i ask?

What hardware solution did you use for the Hard Drive Temp Cable?

Thanks!

Charles

From what I read he did not correctly address the issue, he uses software probably an app such as SMCFanControl.app. Here is what he stated:

"Aside from solving the fan issue with software - alll worked fine."

I replaced my 500GB Seagate drive with a 2TB WD Caviar Black and replaced sensor cable with an optical drive cable (P/N 922-9214). The original 2TB Seagate I first installed immediately showed 1 bad block so I replaced quickly with the WD drive.

That was two months ago and still no problems. I have Temperature Monitor, iStat Pro and SMART Utility installed for monitoring. All three are reporting the same HDD temperature.

i do not feel your feedback is useful, i can read posts for my self thank you,

None - just used software to control the fan.

Our environment is cooler than most in the UK and the machine is not used in a very intensive way. So I am fairly relaxed about the heat levels.

i do not feel your feedback is useful, i can read posts for my self thank you,

I mistakenly answered a post from you, that was my only error. However I will make it point to ignore you.

ok very good, i herd that some people could just use software to control the fan...

maybe apple changed something, so the fan would not just climb to full speed in some models.

other people will have to do something with the Temp Cable First before they can control the speed of the fan,

in my case shorting it allowed me to then control the fan speed with software.

obviously it would be much easier to control it with software with having to modify any hardware.

yes please do so. PLEASE!

That part number is an LCD heat sensor... Is that correct. I hope so I just ordered one.

Controlling it with software is not a viable option for me.