If you can boot to Open Firmware CPU(s) are recognized and OK. OF of 1.8GHz - mainboard is capable to handle 2.0GHz CPUs. Have the same config here (runs with 2.0GHz but at moment with 1.8GHz).
Netproblems are not caused by CPUs. That can be veryfied in OF. OF can handle TELNET and TFTP.

Type in OF to launch a Telnet-server:

Code:

where 0.0.0.0 is the IP of your MAC in your home-net.

Now you have TELNET access from another PC to this address (eg from Amiga or other MOS-machine from shell:

Code:

If you type in different OF-commands and get a reaction, then network-hardware is OK.

To check it you may also boot MacOS.

Fans: Check the connector of your intake-fans. Seems that Mac does'nt get back revolution-signal of fans, so it turns it to maximum (emercency mode). In worst case main-board is faulty. But in that case you can install a small PWM-contoller for manual adjustment in conjunction with PowerMac7FanControl (small DOS-Prog for MOS which can show cpu-temperature, and something more...). I have those problems at drive-bay-fan and backside-fan - they were allways running at maximum - like a jetplane.
If this is the case -> PM to me.

[ Editiert durch Amigaharry2 22.01.2021 - 20:17 ]