XPS 8950, replaced rattling fans in PSU, now computer extremely slow, sensor reading low

The rattling little fans in the 750W power supply of my XPS 8950 were driving me crazy and I’m out of my warranty period.  

I replaced the fans with Noctua NF-A6x25 FLX fans, after reading threads where people used this replacement successfully.  

I had a computer repair store install the fans and solder the wires, red to red, black to black, yellow to yellow.  

Now, computer is nearly silent but it’s extremely slow.  Just starting it up takes forever.   I ran a diagnostic check and it said all 3 of my disk drives had an issue with the sensor “reading (-100c) lower than expected”.  

The PSU fans aren’t running, but I’ve read that’s normal bc these Noctua fans will only start spinning when the temperature is high enough.  

Any idea on what I should do next?