1. How many slots does the iMac have?
2. If I start with 16GB based on 2 8GB sticks, can I just add 2 more 8GB sticks later on if I need them to max it out at 32GB?
3. I bought the iMac from Apple with 8GB. Can I use this 8GB along with the 2 8GB sticks?
which iMac did you order? Only the 27" has user replaceable ram..
If you plan on taking up all 4 slots with 8Gb in each, make sure you buy 1.35v Ram, otherwise you will be facing endless Kernel panics.
User replaceable according to Apple (ie. won't mess up warranty)? I pulled the plug on a 21.5 with 8GB, which will suit me just fine, but I thought I had seen a video last night of someone opening one up to replace the RAM.