Speccy is naming my (dual-core) AMD Phenom-II X2 model 555 ("Callisto") CPU as a (quad-core) Phenom-II X4 B55 ("Deneb") CPU, although it does show correct number of cores, correct stock MHz, correct cache sizes/levels/associativity, and so on and so on.
This is in an (admittedly aged) Dell Optiplex 740E with latest BIOS, in which that very same Callisto CPU has been working absolutely fine for over 5 years, first under Windows 7 and subsequently under WIndows 10. However, the Dell BIOS doesn't quite recognise this CPU - it knows it is a Phenom-II of some kind, as it can initialise it and