It's interesting that there is a second socket silkscreened on the board. I assume that this entry is your board?

https://theretroweb.com/motherboards/s/zeos-coral-max

It's quite a nice second generation P5 board.

- Alex

Not in front of board atm so just used retroweb/UR images. But same board. I posted that link in OP btw. You missed it 😀

Adding the second socket is definitely part of the plan. First step, get it working though.

Those sockets in upper right of pic are also interesting - looks like the SCSI controller is optional and you need to populate them for that.

As for not booting, you say:

wondering if maybe the wrong cache module got installed

Obvious first step: try to boot without cache module.

The slot looks like standard COAST, but most (if not all standard) COAST modules are PLB cache, whereas the i430NX can only use asynch cache. If there's a PLB module in there, that would explain a lot...

Tried no module, no dice

Did you connect the 3.3V PSU-connector?

majestyk wrote on 2022-12-01, 15:22:

Did you connect the 3.3V PSU-connector?

Of course 😀

My family had a Zeos 386 that I played all the Lucasarts stuff on. P5 must have been the very end for them as a company. Everything after that one would have been Micron branded.

Do you have a POST card? If so, what does it say when attempting to boot?

Also, another double-check: this is an i430NX board. NX only supported FP DRAM, not EDO. Are you using FP? Or could your SIMMs be EDO?

dionb wrote on 2022-12-01, 17:28:

Do you have a POST card? If so, what does it say when attempting to boot?

Also, another double-check: this is an i430NX board. NX only supported FP DRAM, not EDO. Are you using FP? Or could your SIMMs be EDO?

Fp, that may be the issue.

Wasn’t aware of that.

I do have a post card. I forget what it shows. I am going off memory from my attempt to get it working a few months back. Lemme set it up again and try the fp ram idea.

Okay, I’m in front of it again.

How’s this cache stick look?

Edit: note the color coded pinout on the extra power plug orange for 3.3v and black for gnd.

This memory okay?

Any suggestions for a removable battery clip that will fit?

I’d also like to get the scsi working eventually. So if anyone knows a card that I can order and rob a chip and crystal from, lemme know.

It could be, for example: AMD PCnet SCSI Am79C974

Sphere478 wrote on 2022-12-02, 03:46:

This memory okay?

Look up the chip codes: tms427809

The '4' suggests Fast Page, which is good. Having a bit of trouble decoding the rest (or finding a data sheet). That '2' might indicate low-voltage 3.3V chips, which isn't good on a 5V board like this. But it might not...

Don't you have two bog-standard 4MB SIMMs with 8 (or 9) 4400 ICs on them? That's the gold standard for FP that anything should work with.

Memory looks to be 3.3V EDO: https://www.digchip.com/datasheets/parts/data … 427809A-pdf.php
Searching for 'CR2032 vertical battery holder' seems to return various holders that look like they might fit.
There was another thread with a dual socket 5 recently, may be something useful there to help with adding the extra socket: Adventures in rebuilding a BIOS for the Sprint P5N-DP V3 (rare dual socket 5 board)

Could be fun.

dionb wrote on 2022-12-02, 12:30:

Look up the chip codes: tms427809 […]
Show full quote

Sphere478 wrote on 2022-12-02, 03:46:

This memory okay?

Look up the chip codes: tms427809

The '4' suggests Fast Page, which is good. Having a bit of trouble decoding the rest (or finding a data sheet). That '2' might indicate low-voltage 3.3V chips, which isn't good on a 5V board like this. But it might not...

Don't you have two bog-standard 4MB SIMMs with 8 (or 9) 4400 ICs on them? That's the gold standard for FP that anything should work with.

These are the only other possibilities that I own. I’m pretty sure that top one is what you are talking about

snufkin wrote on 2022-12-02, 13:28:

Memory looks to be 3.3V EDO: https://www.digchip.com/datasheets/parts/data … 427809A-pdf.php Searching for 'CR2032 vertical batt […]
Show full quote

Memory looks to be 3.3V EDO: https://www.digchip.com/datasheets/parts/data … 427809A-pdf.php
Searching for 'CR2032 vertical battery holder' seems to return various holders that look like they might fit.
There was another thread with a dual socket 5 recently, may be something useful there to help with adding the extra socket: Adventures in rebuilding a BIOS for the Sprint P5N-DP V3 (rare dual socket 5 board)

Could be fun.

Ooo nice thx!

I haven’t tried setting it up yet again. Doesn’t seem like much point without a new battery and correct ram.

What is the largest memory configuration for this board? I may just order some from ebay.

Is there such a thing as 128mb fpm sticks?

This board only supports 64mb cachable doesn’t it?

So what? 8mb x 4 sticks optimal?

Was really hoping for more..

Edit:

https://theretroweb.com/chipsets/1357

Oh wow according to this, 512mb cached 128mb sticks is max, catch: fpm only.

Apparently the 512mb capable tag is integrated

Just ordered 4

It’ll honestly be nice to not have that odd simm slot populated haha

Sphere478 wrote on 2022-12-02, 16:43:

These are the only other possibilities that I own. I’m pretty sure that top one is what you are talking about

Looks like the memory you've ordered is suitably overkill. For reference, the sticks in that photo look like a couple of 4MB and a 16MB, I think they're all 5V FPM (417400 datasheet calls it Enhanced Page Mode, which from a quick skim looks like FPM). The pair of 4MB are probably useful for testing. Just noticed that the manual from that RetroWeb link in the first post says the maximum RAM is 384MB. So it's possible that board doesn't support 128MB sticks and might just see them as 64MB.

Manual also says the cache needs to be 3V. Datasheet (https://datasheetspdf.com/pdf-file/537700/All … uctor/AS7C512/1) for the chips on the stick in the photo gives recommended supply voltage as 5V. But it also says that data is retained down to 2V, and any signal above 2.2V is read as '1'. So it might be a good idea to check what voltage the Vdd pins on the socket are. When the manual says 3V SIMM it might just mean the signal levels rather than supply voltage. But as dionb suggested, probably best to get the board started without cache to start with.