Help fix my Robotron! RAM error and no video..

I wouldn't worry about the resistor. It's normal for it to get warm since it's dissipating heat that's why they used a 5W part. Did you ever measure the 5V using the AC setting on your meter? What did you measure?
 
I checked at the chips with the DMM switched to AC and got a spike of 0.6 and quickly dropped to 0.000 and stayed.
 
OK, I would say you don't need to look at the 5V power supply anymore then. I had a similar issue with my Robotron, showed ram errors but when I would replace the chip it would still show the same ram was bad. Also during the rug pattern there would be vertical columns of the screen that were more/less red and much less random than the rest of the rug pattern. Turned out to be one of the decoder roms either 4 or 6 was not making good connection in the socket. I removed then re-installed both roms and the problem went away. I know someone in this thread mentioned this but not sure if you did this or not.
 
You don't have a logic probe correct? If not I'm about out of ideas. If you do I could walk you through more troubleshooting. First place I would look is the video blanking and sync circuit.
 
Yeah, don't have one if those. Oh well, thanks for all your help. Guess I'll just take the game to the dump.
 
A lot of people here fix those boards, including myself. Might be time to ship them off.
 
I'll most likely have to send it out. I'll take some recommendations on who to send it to.
 
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