It's the right kind of RAM, showing up in About this Mac. Works fine when I restart, stays going as long as I am working, then shuts down when I walk away for a few minutes. Upon restarting, I get the little gray box with Your Mac shut down because of a problem error message. Anybody else run into this?
iMac, OS X Yosemite (10.10.3)
Sounds like incompatible RAM by brand and/or quality. Macs are picky about RAM quality and, although a module may meet the basic specs, it may still not work. Going way back to when Apple switched to Intel processors, we starting seeing reports of bargain RAM not working in Intel-powered Macs even though their speed ratings were correct.
Kingston ValueRAM is the worst offender historically, and we see a number of simlar problem reports with Corsair RAM. In almost every case, replacing that RAM with RAM from Crucial or Other World Computing fixed the problem.
So, can you tell us what RAM you bought?
Actually, it is Crucial, which, from what I had read, should work fine on this iMac. Thank you very much for responding to my question!
The correct Crucial RAM for your model should work.
iMac: Memory specifications and upgrades - Apple Support
Did you buy it directly for Crucial or at least use their web site to verify that it is the correct RAM for your model...?
http://www.crucial.com/usa/en/apple-memory
If you bought the RAM directly from Crucial, then contact them for support and/or replacement RAM.
If you did not buy the RAM from Crucial, then return it and buy some directly from either Crucial or OWC.
So, took the new RAM out, and machine running perfectly again. Returned new RAM, which my iMac did recognize but obviously did not like, and re-ordered from Crucial, using their handy identifier tool. Fingers crossed that RAM directly from Crucial will fix problem. Thanks to Allan Jones and den.thed.
Installed addl RAM on late 2013 iMac, now shuts down randomly
