Thinkpad R52 will not post past first Bios diagnostic screen

[hcooll3]

I have a thinkpad R52 with an R51board in it. The thinkpad is a type 1847 and I switched back and forth between soldering two bios chips that performed the same
first bios diagnostic screen when pressing escape while in logo screen. The Ibm blue button will not take me to bios and I have the R51 bios prgrammed in. Both chips have the same first bios with one that was on the board when I purchased it. The ending errors I get are 0271, 0187, and 0191. I still have the original board that came in the laptop although I assumed something was wrong with it after plugging in a vga cable that crossed two wires and the screen went black. I wonder if there really wasn't
anything wrong with the board because sometimes the screen stays black on the new board until I unplug the power and cmos battery or just wait a minute to power it back up. Does anyone have a suggestion? Even the suggestion of using the old board again.