No, I don't ever remember a CPU having a BIOS backdoor. CPUs do not have a BIOS. The BIOS is part of the motherboard.
BIOS backdoors have been for recovering the machine after the admin password for the BIOS is lost. Phoenix, AMI, Award, Dell and Compaq have all been guilty of that - with simple passwords too. But these all required physical access to the machine.
The most nefarious, however, was DEITYBOUNCE from the NSA installed via Malware but only on Dell PowerEdge 1850/2850/1950/2950 RAID server series.
I suppose you are thinking about the Intel Management Engine and AMD's Platform Security Processor (PSP) but again, not part of the CPU but part of the motherboard.
Intwl intentionally made their naming system more difficult to know which generation, right before this.
No, I don't ever remember a CPU having a BIOS backdoor. CPUs do not have a BIOS. The BIOS is part of the motherboard.
BIOS backdoors have been for recovering the machine after the admin password for the BIOS is lost. Phoenix, AMI, Award, Dell and Compaq have all been guilty of that - with simple passwords too. But these all required physical access to the machine.
The most nefarious, however, was DEITYBOUNCE from the NSA installed via Malware but only on Dell PowerEdge 1850/2850/1950/2950 RAID server series.
I suppose you are thinking about the Intel Management Engine and AMD's Platform Security Processor (PSP) but again, not part of the CPU but part of the motherboard.