TobyRieper
Student
Heyy folks, I'm new here and would just like to greet everybody on these forums. I am helping out a firend who runs an arcade and needed some help with the model 3 videoboard. According to this help document over at aussie arcade forums (https://www.aussiearcade.com/forum/...logs/94380-sega-model-3-step-2-0-repair-guide) I have a faulty IC12.
The 'Polygon Memory, IC70 and IC71 fail the test and according to this guide the step 2 boards use a single IC (IC12) instead of the two afformentioned chips. I cannot find these chips NEC D4811650GF-A12 anywhere online apart from obscure Chinese sites. I read an article that said these chips can be found on an old Compaq laptop motherboard (https://www.techrepublic.com/blog/c...n-ultrabook-from-1999-the-compaq-armada-m300/).
The Mobo arrived today, alas the SGRAM chips are different! Instead they are Siemens HYB39S16320TQ. They are the same dimensions with a near identical pinout. Could I use these slightly different chips instead? If anyone could have a look for me and see if these are a compatible replacement that would be great as I'm not too clued up on the ins and outs of RAM chips. Replacing them is not a problem but finding the part is!
Here are the links to the datasheets:
https://www.usbid.com/assets/datasheets/8C/upd4811650.pdf
https://www.datasheetarchive.com/pd...df521f241dbd9effe52&type=M&term=HYB39S16320TQ
I really appreciate any help anyone can give.
The 'Polygon Memory, IC70 and IC71 fail the test and according to this guide the step 2 boards use a single IC (IC12) instead of the two afformentioned chips. I cannot find these chips NEC D4811650GF-A12 anywhere online apart from obscure Chinese sites. I read an article that said these chips can be found on an old Compaq laptop motherboard (https://www.techrepublic.com/blog/c...n-ultrabook-from-1999-the-compaq-armada-m300/).
The Mobo arrived today, alas the SGRAM chips are different! Instead they are Siemens HYB39S16320TQ. They are the same dimensions with a near identical pinout. Could I use these slightly different chips instead? If anyone could have a look for me and see if these are a compatible replacement that would be great as I'm not too clued up on the ins and outs of RAM chips. Replacing them is not a problem but finding the part is!
Here are the links to the datasheets:
https://www.usbid.com/assets/datasheets/8C/upd4811650.pdf
https://www.datasheetarchive.com/pd...df521f241dbd9effe52&type=M&term=HYB39S16320TQ
I really appreciate any help anyone can give.
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