Answer to "Can I Mod an early 2009 24" iMac to external monitor?"This may be late, but YES. The answer is YES. YES you can convert your old iMac (or laptop or anything!) to a standalone monitor. I did this sucessfully with both an old 17" Powerbook screen, and an old 2007 24" iMac. 1) Gut the iMac completely. Remove all components from the shell 2) Install a VGA Control Board. Based on the model number you provided, this would be your best bet: http://www.ebay.com/itm/M-NT68676-2A-HDMI-DVI-VGA-AUDIO-LCD-Controller-Board-For-17-1-LP171WU1-A4K2-/191097196152?pt=LH_DefaultDomain_0&hash... 3) recycle screws and screw posts from the old guts to secure the VGA control board. You can also use plumber's tape+bolts, or just hot glue and duct tape. 4) The power supply. Most VGA control boards take the standard 12V that eeeevvvveeerrrryyything uses (usually 5.5x2.1 plugs). So find any old wall-wart or power supply you have lying around, just make sure your 12v psu has sufficient amperage. I placed the PSU inside the iMac case, and soldered the power plug to the inside of the iMacs...