Ok, I'm going to have to call in help on this one. I'm working on a Stern-200 mpu, yes had battery damage, all cleaned up, reset section rebuilt, new machine pin sockets at U8, U11, U13, U14. Board was locked on prior to the work. Jumpers set for U2+U6. Working with known good CPU,PIA,U7 and 5101 chips as well as nvram options. I'm getting the board to boot, 2 flashes and fail. I've burned Leon's version 4 ROM and get the pulse as expected. Then when hitting S33 I get the control light on dim and the mpu board light off, indicating bad U8 memory. I've checked voltages at the chip and I have some abnormal voltage, but can't find what's pulling them down. All good except pin 5, should be 1.5v, I'm 2.35v, pin 7 should be 2.5v I'm getting 1v, pin 20, I'm getting 2.4v instead of 3.5-4v. these voltages are the same back at the CPU (U9). I have checked for shorts on all pins on U6+13. I have good continuity on all pins listed on pinwiki except U8-20 to U18-7, but do have it to U14-10 like the schematic says I should. Removing both PIA chips and all memory chips I get the same voltage reading so it's not them pulling it down. At the A0-A7 resistors I have the 5v on the right side of R-129, but 1v on the left side I swapped the resistor just because, no difference. Any thoughts on what to check next? Thanks, sorry for the long post, wanted to provide as much info as possible.