I have a mid 07 iMac that I just upgraded the memory in and now it wont reboot. I had two 1 gig and switched to two 2 gigs. I can replace one of the 2 gigs with one of the original 1 gigs and it will start and shows in "about this mac" that I have 3 gigs??? Then take the 1 gig back out replace with the other new 2 gig and wont reboot again.
Any help would be appriciated!
Dana
iMac, Mac OS X (10.7.4), Mid 20007
Either the RAM you purchased is not compatible with your iMac, or one or two of the RAM sticks is not inserted properly.
What are the specifications of your iMac and of the RAM sticks you purchased?
Put your original memory back in, navigate to this website and let their system scanner evaluate your system, check to see if you have the same memory they recommend. Some cheaper memory manufacturers do not make memory that will work in Macs. They are finicky about the RAM.
I just read somewhere that older (2006?) iMacs can take 4GB and will show that in About this Mac, but only use 3GB.
http://support.apple.com/kb/HT2821
Could that be your issue?
I came here trying to find out why mine won't boot at all after the upgrading from 2x1GB to 2x2GB.
Sorry, my link didn't copy in my previous post, here it is: Crucial at
RRFS I I can't put the original in when I did it was blank. When I went to apple they told me the original had gotten fried. Kevin sadly I am getting suspicious of that same thing
Dsimagry the chips match the original except instead of 1 they re both 2 gigs the first set of chips were monster the second set were patriot friend told me to order some owc since apples can be picky so I have some of them on the way.
I hope this isn't too late, but what worked for me was to boot with a 1 GB and a 2 GB RAM stick installed. Then I shut down and removed the 1GB stick and rebooted with only the 2 GB stick installed. Then I shut down and added the other 2 GB stick. It booted and shows 4 GB total RAM.
I've also heard you should wait for thirty seconds after hitting the power button to let your iMac recognize the new RAM.
iMac Mid 07 won't reboot after memory upgrade
