Odd bios on V7 not booting DVD-r

[L-dubb]

I have been running into V7 systems w/ odd looking bios # on the bios chip. Like B 10070 2345 and other odd combinations. And on every one Once I install a chip it wont read DVD-r at all. It boots original DVD, CD-r back ups ps1 and ps2, nd original CD but no DVD-r. I have put 3 different chips in these system 3.1, M2pro 1.3 and DMS3 2.0 and all have the same result. I tried adjusting the laser and that didnt help. Has any one else run into this before?