Getting a u25 RAM error when booting up my F-14 Tomcat. I socketed and replaced the RAM with a 6116 chip. Still having problems. The strange thing is that if I powercycle the machine quickly, it works fine. It also remembers settings correctly. It's pretty clearly something on the CPU board. What exactly are the steps it goes through to self test that RAM?

Not really seeing corrosion here, but I don't like this chip for some reason. The last one in the box always makes me wonder if someone put it back because it didn't work. No other 6116 chips, so I'm gonna jumper for a 64.

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Oh, duh. Well, poop. Gonna check that voltage then.

Hmm. 4.94 at cpu board. Not spectacular, but is that really enough to cause problems?

There's a hack to the switch area that honestly makes me laugh, but is functional. Some past guy didn't have a resistor array, so he just made one out of a bunch of resistors. Otherwise, no previous work. That is a new socket. I'm beep testing lines as we speak. Looks like the processor goes through u16 for the data lines, and u11 and u13 for the address bus. Doing some beep testing to make sure there's no broken traces, but those are my next targets.

And, neither of those are in stock. I guess this is tabled until I get some chips in. Always tempted to pull from old boards, but that just complicates things.

Update: Was a bad U16. All fixed!