Review on OWC 1GB PC5300 DDR2 667MHz SO-DIMM Memory: Compatible with MacBook Pro, MacBook, iMac, and Mac Mini (Intel) Models by Stanley Molden

I bought these RAM upgrades for my mid 2017 imac. If both cards are installed, the Mac will not boot. I tried with an installed original and a new one and then it booted fine but only had 3GB (I wanted 4). I then replaced the new one with another to try and troubleshoot and of course the Mac doesn't recognize the RAM and won't boot. Swapped two new ones and everything worked. So obviously one of the new RAM cards is not working. main fright. I will send these back as soon as possible.