The hardware manuals (http://ps-2.kev009.com/pcpartnerinfo/ctstips/fdbe.htm use the link to get the name then search it) just says the sizes and speeds, not types.
Being a 486-33/66 I would say no to EDO. You could try some (remove the FPM first) as a test but my gut says no....
a reference on 486 and EDO: Re: FPM vs EDO memory for 486 (SiS 85C461)

Thank for the input!

In the hardware manual it says this:

Specifications: 72-pin; 32-bit or 36-bit; 2MB, 4MB,
8MB, 16MB, or 32MB; 70 or 80 ns for 25 or 50 megahertz (MHz), 70 ns for 33 or 66 MHz; gold contacts;
DRAM.

I have no idea what frequency this ram is running at. Had a look in the BIOS, but it didn't specify further, only gave the amount.

It's probably as you say.

InterClaw wrote on 2024-01-06, 21:48:

Thank for the input! […]
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Thank for the input!

In the hardware manual it says this:

Specifications: 72-pin; 32-bit or 36-bit; 2MB, 4MB,
8MB, 16MB, or 32MB; 70 or 80 ns for 25 or 50 megahertz (MHz), 70 ns for 33 or 66 MHz; gold contacts;
DRAM.

I have no idea what frequency this ram is running at. Had a look in the BIOS, but it didn't specify further, only gave the amount.

It's probably as you say.

When the machine has a DX-66 the system bus is 33MHz. So the RAM runs with 33MHz.

InterClaw wrote on 2024-01-06, 21:48:

[...]

I have no idea what frequency this ram is running at. Had a look in the BIOS, but it didn't specify further, only gave the amount.

It's probably as you say.

As a rule, if documentation does not specify EDO vs FP, that means it pre-dates EDO and will only support FP.

So you need FP DRAM SIMMs for 70ns or lower.

As for parity - you don't need it, but that 3rd/5th+6th/9th/17th+18th chip won't hurt either. Just ignore parity or not on SIMMs for this system.

Excellent! Thanks for the explanations about the frequency and latency. Then I know that parity chips shouldn't be a problem. That makes it somewhat easier, but I will stay away from EDO as suggested.