Please accept my apologies because I know the following has been posted before, but I've run several searches and can't find it.
I'm about to purchase a new iMac. Since the return time is limited, is there a standard set of functions I can run or specific things I should check to make sure there are no problems once it arrives and is set up?
Check the following, but keep in mind that some level of dead or stuck pixels are acceptable to the manufacturer. Some level of uneven lighting or bleed is not unusual and it's up to you to decide whether it is going to bug you in the long run. If you send it back for relatively minor defects your replacement may be worse then your original.
Check exterior for scratches, scuffs and dents. It's possible that there may be some dust or hand prints between the LCD and the outer screen cover. This cover is easy to remove and clean. The video below is funny, but demonstrates how to do. It's up to you if you want to return it for this kind of fault. If its an otherwise perfect Mac I would just clean it myself.
http://www.youtube.com/watch?v=wDcmG73xPzs
Check the stand for proper function. You should be able to reposition the screen and it stay where you moved it. The stand should not be loose.
Check Screen for stuck or dead pixels.
http://www.ekimsw.com/products/lcdtest/
http://www.jscreenfix.com/faq/03-how-do-i-check-for-stuck-pixels
Check for uneven backlighting and bleed. In a dark room and with a light colored solid background check for uneven light distribution across screen and with a solid black background look for bright areas on the edges.
Check for solid color irregularities. Set the background to solid white and look for color hue changes in regions around the screen.
Sound check. My new iMac is completely silent unless I put it under a heavy load, which it responds to by causing the fans to whisper a little. The HDD should be silent except for a very slight spinup noise when it initially spins up from a cold start or sleep. In a completely quiet room I can hear it, but normally I don't hear it above the ambient noise in the room. The speakers should not make any hissing, buzzing or clicking.
Enjoy your new IMac
