I've reformatted and posted this procedure with pictures on my web site. If you want to print it that format may be better printed than this thread. With web.mac.com going away, pics are gone from this thread. It is under "Tech Articles". OctoMac While this procedure is not for the faint of heart, all said it was not difficult by any means. If you are comfortable with taking things apart and can learn how they go back together as you take them apart, then there is no reason not to attempt this. Standard disclaimer, proceed at your own risk, warranty probably voided (although there were NO 'warranty void if broken' stickers affected by this) etc etc. Goal: Upgrade the internal HD with a much faster and larger drive. I went with a 500gb Seagate 7200.10 Perpendicular Technology 7200 rpm Sata drive. I went with the 500 as it was a much better MB/$ ratio than the 750... and it was cheap... $80 bucks. That said, here are some pics and writeup for your enjoyment: Before: 24" iMac with stock/entry level 320 gb HD. Stock drive is an 8mb western digital WD3200AAJS (blah) First off, taking out the glass is trivial... it's LIGHT and takes very little force. I used two (could have made it with 1) suction cups with hooks to let you hang stuff on glass with. Side note: One of my concerns in doing this upgrade was introducing dust between the LCD and glass. I avoided this by using a can of compressed air and gently blowing off any dust on the LCD and inside of glass before reinstalling the glass. Glass pulled out: notice LCD itself is glossy: Next remove the memory slot cover on the bottom. After that, simply unscrew all the screws along the edge (under the glass). There are 12 screws, 3 different lengths. Just pay attention to where they came from, but truly they only fit in the right holes (pick one too short, it'll be obvious, etc) Bezel/Face off: Inside of Face - Notice the magnets: iSight camera - cable with inline plug... easily unplugs: Now the only part that is slightly tedious - The LCD removal. The LCD is attached with 8 Torx screws. There are three cables that connect the LCD to the computer. While you could just disconnect 2, I think it is worth just unplugging all three and removing the LCD to make working in the unit easier. One plug (DVI) is actually screwed in, very small torx... Watch the SMALL screws: Second connector - 4 wires... lower left, easily unplugged (plug on the right): Worst connector of the three - Power to the LCD. It is a bit tight fitting, much worse getting back in than out: UPDATE: One member found that he could peal back the tape on the LCD itself and unplug from that side, much easier way to disconnect the LCD, no wiggling required! Stock Drive... interesting thing, the pad with the wire going into it. This is a thermister for the temperature monitoring chips/system in the iMac. Not a big deal, just have to transfer the mount to the new drive. To remove the HD, 2 bolts (torx) must be removed, the other two mounting holes on the HD are posts that are removed after the drive is out. The clip for the thermister peels right off Hard drive out. Note the posts, they are just screws with no heads, taken out with a torx. HD is out: Thermister clip installed on new drive: Pop out Thermister: Reassemly is just the procedure in reverse... screw in the posts to the new drive, place the thermister clip and install it. Then simply slide the thermister back into the clip and reinstall the foam protector over it as before: From there, everything in reverse... the power plug for the LCD is a bit of apain to get back it, just takes a little patience. The rest goes together quickly. The whole procedure took me about 45 minutes. System is noticably faster both in booting and loading apps. Definitely happy with the results!