Any have experience mixing a 2.0Ghz and a 18.Ghz CPU in a G5? The reason I am asking is because I had 1 sporadic CPU (dual 1.8Ghz) and I wanted to get it back to being a dual system since as a single G5s are slow as molasis. So I ordered a 1.8Ghz CPU off of apple components that was listed as one that was compatible with the RDU code 1.8s. It just arrived and I looked at the code which was QJL which I didn't recognize and wasn't listed as being compatible with my CPU. So I looked it up on their website and it comes back as a 2.0Ghz CPU (and other websites too). https://www.applecomponents.com/ite...z-for-dual-config-v-2/?pn=1&s=QJL&per_page=30 So I plugged it in figuring "great, now I gotta return it because it wont recognize the second CPU". So I turned it on and just figured it would show me single 1.8Ghz G5 in the profiler. It started up and the fans were going wild as expected, but when I checked it shows dual 1.8Ghz CPU. And activity monitor is showing me 2 CPUs right now. So does anyone know if you plug a 2.0Ghz into a 1.8 system if the 2.0 throttles down to a 1.8 and works anyway? The other thing I figured was maybe the heatsink was damaged and they replaced it with one from a 2.0 (it is actually a little crooked)... but that doesn't make sence because both the sticker on the heatsink AND the daughter card are the same and say QJL. Anyone have any ideas? I still have to test it for the whole day though. The bad CPU would work fine for the first hour of being installed and then 50% of the time fail to boot up and the other half it would freeze and kernel panic after 2-5 minutes of being on. Switching CPUs (running 1 at a time) seemed to confirm it was the CPU and not the motherboard or the socket.