Stargate RAM Errors - Is RAM IC temp any indicator?

Just started working on boards after a 25+ year hiatus. I'm confident in my soldering skills, but not proud. Need some practice before I put something out in front of the heartless critics in here.

"Clean your flux you filthy animal!
Hey Sir Whets-a-not, you call that a fillet?
Good God Man! How many rolls of solder am I looking at here???
Did you strip that insulation with your teeth? And it's little singed; Did you use an iron or an arc welder?"
I'm gonna keep these for use later. They"re pretty good!
 
Just started working on boards after a 25+ year hiatus. I'm confident in my soldering skills, but not proud. Need some practice before I put something out in front of the heartless critics in here.

"Clean your flux you filthy animal!
Hey Sir Whets-a-not, you call that a fillet?
Good God Man! How many rolls of solder am I looking at here???
Did you strip that insulation with your teeth? And it's little singed; Did you use an iron or an arc welder?"
I leave the flux on my boards just to bother people
 
I've purchased a lot of parts from Unicorn and never had an issue. Maybe just got a dud, or something still not 100% on the system.

~Brad
Just wanted to report back that Unicorn did promptly refund me after I explained the failure. Didn't want anything to reflect poorly on them.

And for the last week, Stargate has been running like a champ and kicking my ass daily.
 
no. TTL has an operating range of 4.75-5.25V. whoever told you it's perfectly acceptable to run TTL chips up to 7V is wrong.

are you running a switching power supply or linear? never mind the ram temperatures, 4116s run hot, they're little 16 pin chips powered with +12V, of course they're going to run hot. any mischief relating to "omg replace them with 4164 rams immediately!" would result in catastrophe if you're running 5.6V through them.

and where were you measuring the voltage at? don't even bother trying to measure the voltages at the rams. whoever was proposing that years ago or reflowing solder to those poor quality headers the games came with were also wrong.
Do the input voltages need to be altered if the 4116 are replaced with 4164's ?This board has rams all replaced with 4164s and I am trying to figure out why they ran 5 v to what was otherwise , the gray and yellow 12 v on my hacked pcb power connection thanks Screenshot 2025-10-06 at 4.34.27 PM.png
 
That adapter was made by the famous Bob Roberts! Pin 8 is were all 3 DRAM are powered, the 4116 used 12v and the rest +5. I think it's also a good idea to tie pin1 to either ground, or +5 in case someone wants to use a 41256. Even though A7 (or A8) is not used on these boards, you have to keep them 'tied', either high or low to prevent floating. if the address line(s) float, you run the risk of data corruption.


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That adapter was made by the famous Bob Roberts! Pin 8 is were all 3 DRAM are powered, the 4116 used 12v and the rest +5. I think it's also a good idea to tie pin1 to either ground, or +5 in case someone wants to use a 41256. Even though A7 (or A8) is not used on these boards, you have to keep them 'tied', either high or low to prevent floating. if the address line(s) float, you run the risk of data corruption.


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I had boards in the past with 4164 ram where I had to mod A7 to be grounded or else they had pretty bad artifacts being tied high. I would venture that means something else is bad.

I'm also a proponent for 41256 ram if you want +5V only ram. 4164 has a variety of weird complications pertaining to operating voltage in my experience.
 
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