I don't think they made DRAMs in that time or we would be seeing them very commonly. But they certainly did DRAMs at some point, there appears to have been a lawsuit involving UMC stealing design from Micron, in not so distant past but this won't help with the problem at hand 🤣.

All UMC build is a thing I'd like to do aswell. Unfortunately UMC also never made any PC sound chips and their VLB video chips are not exactly common either, these are the two things I am missing for my build. There are modems with UMC chips but that isn't quite a sound card though 🤣

I didn't think of a soundcard yet, I just assumed that would be a stretch from their core business to something with FM. I didn't know they made a modem, that is something interesting.

DRAM seems to be a close thing to SRAM that the did indeed make.

Oh well. I thought I would ask.

UMC built a lot of their own and ic's for others until 1995. Dram chips from Vitelic or Mosel before 1996 is most likely made by UMC but not labeled as UMC. They did make SRAM with their own label.....
According to wiki MediaTek was part of UMC until 1997, if you find a sound card with a MediaTek chip dated before 1997 it would be UMC though have never had one personally AFAIK...
Added: have read diff accounts of who made the MediaiVision PAS ASIC chips in early-mid 1990's and it is possible it was UMC.

UMC the foundry 100% manufactured ram at some point, if not fully commercially then to hone fabs capabilities.
UMC design house? There is very little margin in RAM, UMC engineers mainly did value add products.

Tiido wrote on 2024-05-21, 03:12:

All UMC build is a thing I'd like to do aswell. Unfortunately UMC also never made any PC sound chips

UMC was trying to avoid more lawsuits at this point in time. They are the original source of famiclone chipsets https://www.upi.com/Archives/1994/01/11/Ninte … /9249758264400/), and its highly likely they cloned Toshiba 386 chipset Identifying PCChips 386 era chipsets. After lawsuits they span clones into smaller companies. Its possible Princeton Tech (PTC) cloned Yamaha OPL2/OPL3 chips were build in UMC fabs, and maybe even joint designed Re: Master Boomer J5QMF-00 Sound Card

Yeah, they did lot of stuff for other companies so that is a way to get UMC in spirit for the parts that were not actually branded as such 🤣.

I am familiar with their productions toward pirate market, and in form of unbranded stuff too for other companies, i.e There's a clone chipset for Mega Drives with SE-9x markings. Those are UMC manufactured parts (and they seem to outperform japanese made original parts, lower noise better overclockability etc.). It isn't particularly difficult to identify UMC manufactured chips, like others, they also have distinct font and package features.