The issue still sounds like a CPU/socket problem. Of course it may be a reset issue. Unplug the keyboard as well and fire it up. If you can, verify the clock it spinning and that the reset line is in it's proper state. (One state on power up and to the other state about 1/2 second later.) Pin 40 is reset, I can't tell where the clock signal is from the diagram I have here. (see below) Since you have replaced the socket, I'd take as close look at the CPU socket as possible. Get a bright light and magnifying glass and have a look-see at the connections and on the main board and immediate area. Look for a crusty appearance that may indicate corrosion between two contacts. Look for a tiny solder blob that may be shorting the clock or reset pins. See if rewetting the socket helps. For checking the connections, use a toothbrush to get under the socket and around each pin to see if there is something to be dislodged. Look for a blob of corrosion or solder. Thankx, Ed Wayne Stewart wrote: > Good idea but after pulling the rest of the cards I tried a regular 65816 with no luck. Some time ago I replaced the socket with a machine contact socket. Back then I had doubts about a regular socket making solid contact with the cable. /=============\ /=============\ VP I1 40I RES Vss I1 40I RES RDY I2 39I VDA RDY I2 39I o2 (OUT) ABORT I3 38I M/X o1 (OUT) I3 38I SO IRQ I4 37I o2 (IN) IRQ I4 37I o2 (IN) ML I5 36I BE NC I5 36I NC NMI I6 35I E NMI I6 35I NC VPA I7 34I R/W SYNC I7 34I R/W VDD I8 33I D0/BA0 Vdd I8 33I D0 A0 I9 W65C816 32I D1/BA1 A0 I9 6502 32I D1 A1 I10 31I D2/BA2 A1 I10 31I D2 A2 I11 30I D3/BA3 A2 I11 30I D3 A3 I12 29I D4/BA4 A3 I12 29I D4 A4 I13 28I D5/BA5 A4 I13 28I D5 A5 I14 27I D6/BA6 A5 I14 27I D6 A6 I15 26I D7/BA7 A6 I15 26I D7 A7 I16 25I A15 A7 I16 25I A15 A8 I17 24I A14 A8 I17 24I A14 A9 I18 23I A13 A9 I18 23I A13 A10 I19 22I A12 A10 I19 22I A12 A11 I20 21I Vss A11 I20 21I Vss \=============/ \=============/