Hi guys, Opening a new thread, since this is not a sata question anymore. This is still about the iMac I found in the trash. Now it's up and running, with a PCIe SSD 128Gb and a SSD 256 Gb on the sata port (long story). For the moment, I only have the system (el capitan) installed on the PCIe, and nothing on the sata SSD. No applications yet, no data, no nothing. I thought the computer was really slow, so I did a few tests. First, both SSD had unusually slow write and read speeds (around 200MB/s write and 320MB/s read), which was odd. But ok, why not. But still, the computer was slower than my old PC, which is something like 10 years old. I ran geekbench 4. And got some really strange results: https://browser.geekbench.com/v4/cpu/1182677 and GPU here : https://browser.geekbench.com/v4/compute/265787 I'm running a test on my ram right now with Rember. It's taking forever so I'll come back later with the results (I'm on another machine right now). I tested both SSD already, they are in perfect condition (both are almost brand new). I don't understand what could have happened. My CPU is a single core, with no hyperthreading. So there's no way only one core is working and the three others are down. I saw some other people with exactly the same results when I searched through the geekbench results. I couldn't however find anybody with the same question or getting an answer about a similar problem. I did find some people with low benchmarks on laptops, after the battery had died. So nothing to do with the present problem. What's going on? Is all hope lost? Should I disassemble it and sell it for parts? Reset SMC seems ridiculous, since I unplugged it numerous times already (and no later than yesterday, when I actually changed the powercord because I had to move the computer around and had a free power cord ready somewhere else). Apple diagnostic did tell me there was something wrong with the smc controller, and my fan is indeed going crazy without the macs fan control (everybody was telling me it was a firmware issue, which was odd because the SSD came out of a macbook air). I didn't notice anything weird with the Activity monitor: no kernel activity taking up all the processor. Edit : after 3 hours, Rember gave me the results: ram is perfectly fine. I'm doing CPUTest right now, test type "all", almost done, everything until now was successful. A friend suggested maybe the processor was protecting itself because it was overheating, so I checked the temperature, it's rather cool, so not overheating at all (about 90°, which for me is really not very hot (I'm used to the crazy hot temperatures of my macbook pro late 2011 that would burn my palms)). Somebody else suggested something might be wrong with the ram, but I mean, it's detected, it didn't appear as faulty in apple diagnostic, it passed the rember test even though it took forever (I tried it on my macbook pro at the same time, it took a lot of time too, and I don't have any problem on that computer). Anyway, I'm NOT changing the ram. I already disassembled the motherboard once, I'm not doing it a second time. And before you ask, I didn't damage the processor during the disassembly, I already noticed the computer was really slow before I opened it to put the PCIe SSD inside, but, my fault, I didn't take the time to do the necessary tests, mostly because at that time I was running on an external drive connected via usb 3 and I thought that was the reason the computer was so slow.