Not sure which forum so move if I'm in the wrong forum.
I originally had the Grub for this install on HDB. The install is on HDA. When I reinstalled I chose HDa for Grub. It in fact did install Grub on HDa. The problem is it still boots to HDb first then boots to Grub on HDa then boots HDa from that Grub on HDa.
I thought disconnecting HDb would solve the problem but it didn't. I get to stage 1.5 and then Error 21. Research seems to indicate this is a CMOS error. I have went into CMOS and checked that boot order is correct, CD then HD. Only the one HD is shown after disconnect of HDb. The drive HDa is SATA so no jumper problem. The disconnected drive, HDb, is PATA.