late 2009 imac hard drive Sata 2 or 3?

hey guys, my late 2009 imac hdd is having s.m.a.r.t. status failing
i have to buy a new hard drive but i dont know if it's sata 2 or 3? please help me :/

Welcome to Mac-Forums..

The late 2009 iMacs have SATA 2 drives in them..

thank you very much Raz0rEdge

I have a late-2009 27" iMac as well and these era iMacs didn't have the special firmware or cable for the HDDs..so you can pick up any SATA 2 3.5" HDD and replace your failing one..as long as you get inside the iMac without breaking anything of course..

thank you again
my imac is 21.5 but i think the hdd is just like the 27 right?

Yeah the HD's are the same type and size..so no worries..

thank you

Raz0rEdge said:

I have a late-2009 27" iMac as well and these era iMacs didn't have the special firmware or cable for the HDDs..so you can pick up any SATA 2 3.5" HDD and replace your failing one..as long as you get inside the iMac without breaking anything of course..

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Thats odd, as I have been changing a lot of hard drives in Late 2009 27" iMacs as part of the
Seagate 1TB hard drive replacement program, and all utilised the drives built in temperature sensor, having the sensor cable installed.

Here's a picture of the one I replaced today showing the temperature sensor cable.

Steve, hmm I thought that came in the year after..

I am pretty sure Apple started some of their Proprietary junk with the Temp sensor in 2009. Will check OWC to be sure. It got worse in 2010 for sure.

so i can't pick any hd techiesteve?

Will check OWC to be sure.

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I also thought (possibly wrongly) that the proprietary drives and cable started with the 2010 models. I can't remember where I saw it on the OWC site though. I do know that the OWC turnkey program for the iMac is for the 2010 and 2011 models only. No mention of the 2009 or earlier ones.

zurcfe said:

so i can't pick any hd techiesteve?

Click to expand...

There is one way, but it involves having no temperature sensor, and Apple wouldn't have put one there without a good reason.

If Apple had fitted an SSD instead of a conventional hard drive, they fit a shorting link into the logic board temperature sensor socket. If you utilised the temperature sensor cable to make a shorting link and used a conventional drive, the fans will not run at high speed. I once conducted a test with a non Apple drive and this worked, then refitted the Apple drive and sensor cable.

the problem is, if i buy any hdd the price is 300 reais(i'm brazilian) - around 150$ dollars for an 1 tb hdd
if i ask the guy to buy an "imac hdd" the price is 1000 reais - 500$ dollars for 500gb