NB: posted in other fora as well
Hi there,
Yes many people have done this and upgraded the factory fitted HDD in their 2010 iMac.
I can't speak for other brands but I will relate my upgrade story, the problems I encountered and my current solutions:
I purchased a late 2010 27' quad core 2.93Ghz imac in July 2011, new from the Apple online store (refurbished). Not the latest model but a very beefy machine none the less. I purchased the 2010 model because I knew that the motherboard (MB) shipped with THREE internal SATA ports, not TWO as per the previous model. The third SATA port was there as an option for a configure to order (CTO) machine to ship with an internal 2.5' SSD HD.
Mine did not ship with the SSD but the THIRD SATA port was still on the MB.
The machine also shipped with the standard 1Tb HDD, in this case a Seagate Barracude 7200.12.
I watched several Youtube vidoes and read several tear-down HDD upgrade instuctions, as posted on various Mac friendly web sites.
Upgrading this machine then:
1. I was a little wary of taking off the glass cover. All the instructions suggested I nneded a pair of heavy duty suction cups, usually deicted with red ot orange handles. Fortunately I discovered you do not have to be Superman to take off the glass front. I used one small suction cup, similar to one used in bathrooms to hold soap holders to walls etc. I have subsequently taken off my glass front about ten times, and I have got to the point where I can do it with my fingernail! Just gently push your nail between the glass and aluminium in the middle at the top and work your nail gently to the left or right outside edge, levering the glass towards you. Pull the glass out gently with your fingers and it comes away easily.
2. I had seen that the factory fitted HDD was a 1Tb Seagate so I purchased a 2Tb Seagate Barracude (same brand, similar model) to have a HDD compatible with Apple's temperature sensor arrangement embedded into the firmware of the drive. This proved to be totally UNNECESSARY. I replaced the 1Tb Seagate with the 2Tb Seagate, inserted the temperature sensor plug into the HDD and reassembled the machine. As it booted I reset the PMU and zapped the P-Ram. To my surprise and annoyance the CPU fan slowly throttled upwards to about 5000 rpm, eventually making quite a lot of noise. I assumed the sensor was not inserted correctly so I disassembled and reassembled, only to produce the same results. Frustrated, I disassembled, then reassembled with the old 1Tb HDD in place. This result produced NO SUCH fan spin increase. I thus deducted that the factory HDD has special Apple firmware to interface with temperature sensor to control fan rpm and hence HDD temperature. As I could not duplicate the firmware in my new drive I followed the next logical step. I disassembled then reassembled with the 2Tb HDD, this time 'jumpering' the temperature sensor. As my previous research suggested the HDD fan stayed at a very respectable 1100rpm. This action of course only allleviates the symptom of high HDD fan spin. If the HDD gets hot the fan WILL NOT spin faster. I have yet to solve this issue but I believe software like 'HDD Fan Control' may be the answer. Pity it costs about AUD$30!
I purchased the 2Tb Seagate brand because I had read I had to replace the factory drive with the same brand. This is not the evidence I found. ANY SATA 3.5' HDD will do. One just has to jumper the temperature sensor to stop the fan spin problem, as even if the temperature sensor connector fits the drive, the new HDD will not have the Apple firmware to interface with the iMac MB.
3. I was keen to use the THIRD SATA port so I purchased a Kingston 128Gb SSD, 40cm SATA cable, and SATA power splitter lead and disassembled then reassembled the iMac with the SSD inserted next to the HDD. Disk Drive utility easily formatted both the new 2Tb Seagate and the Kingston SSD, and I spent a few hours 'Carbon Copy Cloning' operating systems to both drives, including using the WINCLONE to back up my Windows 7 Ultimate install and then do an image restore to my new BOOTCAMP partitioned 2 Tb Seagate HDD. I cannot praise BOTH of these software programs enough. I happily donate and then redonate to both of these developers every so often, using Paypal.
4. I upgraded the ram to 8Gb using an additional 2X2Gb SODIMM modules.
Overall I have a very very grunty machine. It boots a little faster than my 2011 256Gb SSD MacBook AIr, at 13 seconds. Other SSDs are faster but they cost more.
I anticipate being able to leave my front glass panel on for quite a while now. I did get sick of fingernailing it off, and then having to dedust it before repositioning it every time. In fact the last 5 times I did not bother replacing and putting it back on, until I had completed and was satisfied with my upgrading tasks.
And finally my experience with replacing HDD in 2010 iMacs.....use whatever brand you like as the new drive you buy will not have the Apple firmware that your old factory fitted HDD does.
