dionb wrote on 2020-02-27, 19:15:

Nitroraptor53 wrote on 2020-02-26, 23:23:

mpe wrote on 2020-02-26, 22:40:

Ridiculous is 128MB RAM in my Macintosh SE/30 (1989 system).

64MB RAM wasn't that uncommon in 486 days if you were doing stuff like DTP in Aldus Pagemaker or QuarkXPress.

How on God's Green Earth did you get that much RAM on an SE/30? Accelerator Card?

Regular SE/30 has 8x 30p SIMM slots. Populate them with 16MB SIMMs and you get 128MB. I did the same when I briefly had an SE/30 back in the 00's.

I didn't think an 80's machine would have native support for 128mb's!

cyclone3d wrote on 2020-02-27, 19:09:

How much cache does the system support?

How much does it currently have?

How many sockets does it have?

8 sockets, 0 chips, no cache. No idea how much the board supports, it's a late (er) mobo though.

What about a riser that converts the old sockets to DIP32?

That wouldn’t work now, would it? The extra pins are probably for addressing. Well maybe it would work, but you would waste capacity of the SRAM.

I would loom up the board and its manual and then try to hunt down the correct ICs.

Edit: http://ps-2.kev009.com/pcpartnerinfo/ctstips/fa2a.htm

Edit 2: this one would fit I think:
http://www.raphnet.net/electronique/nes_vs/as7c256-20pc.pdf

The SE/30 as shipped doesn't have 32bit clean ROM. So I also had to use ROM from Mac IIfx.

Ok, I miscounted. They're 28 pin sockets. Are there 128k chips for those? (8x128k?)

64 and 128KB chips are all 32 pin, 28pins tops at 32KB.

Merged threads.

You require 8 1 MBit SRAM chips as cache plus 1 512 KBit SRAM chip as tag.
I run a 256 MB 486 with 1024 K L2, so all DRAM is cacheable when running in write-through.

My 486 UMC8886/8881 Project (Version 2.0)

Even with less DRAM you feel the difference. It's just because the cache hit rate increases.