Chadti99 wrote on 2022-08-22, 02:17:

What are you guys using for storage on the m919 boards? Recently acquired a 3.4 B/F version and it refuses to boot with my IDE to SD adapter. Although it’s able to detect the drive size in the bios.

In my experience SD to IDE adapters are an absolute crapshoot if they will work properly. I've had the best luck with CF to IDE adapters since they both use the same protocols and are electrical compatible.

The FC1307 based SD adapters have worked quite well for me, this m919 appears to be the first that refuses to boot with it.

Ugh, can’t even get the mobo to boot a dos install disk with a Gotek. Just hangs on “Starting MS-DOS…”

Strike that, pulled the cache module and now GoTek is booting.

Was able to format the SD card after booting dos from the GoTek.

I can now boot from the SDcard adapter and the GoTek but in both cases I have to disable L2 cache. I’ve tried the original 256k module and a 1024k module. Weird right?

Bios timings are decently conservative ?
Running it at 4x40 mhz ?
Board's integration is not the best out there, so you may be hitting some hidden issue with it.

pshipkov wrote on 2022-08-22, 14:05:

Bios timings are decently conservative ?
Running it at 4x40 mhz ?
Board's integration is not the best out there, so you may be hitting some hidden issue with it.

Running 4x33 atm
Most conservative settings
Double checked the jumpers
Maybe just a bad board

Okay , apparently the memory that came with this board is EDO and that option needs to be set in the bios, I’m booting with l2 cache now!

Chadti99 wrote on 2022-08-22, 15:33:

Okay , apparently the memory that came with this board is EDO and that option needs to be set in the bios, I’m booting with l2 cache now!

Excellent! Did that fix your SD card and booting issues?

Yes I’m able to boot from the SD card adapter now. Enable EDO and disable LBA mode seems to be working.

Finally getting somewhere with this m919.

@pshipkov, at what cache and memory timings were you able to achieve the 21.2 Quake score at 180MHz and 1024k cache?

Apologies for the spam of posts, it was a long battle but finally I was able to duplicate pshipkov’s Quake score of 21.2 on the m919 @180MHz and 1024k cache.

Cache Speed = 2-1-2
DRAM Read = 1ws
DRAM Write = 0ws
L2 Cache = WT
*unsure if these settings are stable or the same that pshipkov used

This mobo is a pain, the memory I was originally testing with no longer posts, explain that 🤣. Currently using a 50ns EDO 16MB Samsung module. And EDO appears to be key to achieving the higher memory througput.

Shouldn’t my Doom score be higher? Is this due to the pci bus speed being cut in half? What’s the process to boot with PCI at full speed?

Also notice the Voodoo4 working on this mobo. I don’t think it or a voodoo 3 worked on the other UMC socket 3 boards I have.

No worries about the multiple posts.

Good to see things working !
This configuration very stable here.
Automatic bus divider is tricked into not kicking in by booting with TURBO turned-off.
There seems to be non-cached memory address somewhere between 32-48Mb. Feipoa confirmed it as well. I stay below that range for best perf.

Same BIOS settings here - everything on max except DRAM READ and L2 cache in WT mode.

Very interesting that you got Voodoo4 working on this chipset.
Voodoo3 certainly didn't work on the 2 M919 boards here. Can you confirm that on your side please ? Just in case.

Thanks for confirming!

I’ll pull a Voodoo3 later this week and test.

So for the turbo trick, can I simply jump j12 during boot and then remove the jumper once I make it to the dos prompt?

About the TURBO jumper - yes.
Looking forward for the V3 test.

Chadti99 wrote on 2022-08-22, 21:20:

This mobo is a pain, the memory I was originally testing with no longer posts, explain that lol.

Expect more of that from PC Chips boards.

Chadti99 wrote on 2022-08-22, 21:20:

Also notice the Voodoo4 working on this mobo. I don’t think it or a voodoo 3 worked on the other UMC socket 3 boards I have.

That is curious. I've never heard of a UMC 8881 board working with a Voodoo4. Did the Voodoo3 work as well? Did Windows 9x and NT4 drivers work as well?

pshipkov wrote on 2022-08-22, 22:35:

Automatic bus divider is tricked into not kicking in by booting with TURBO turned-off.

Really? I've always wired the turbo switch to the FSB jumper so that I boot up at 33 MHz, then hit the switch in DOS to increase the FSB. I didn't know it was even easier than this.

pshipkov, the 50ns EDO memory that Chadti99 is using, is this the same 16 MB module you sent me?

feipoa, this m919 board appears to favor Samsung EDO modules. I swapped the 16MB module for a 32MB 60ns EDO module and it appears to work just as well. Actually going from 16 to 32 has bumped my Quake score up to a consistent 21.3, how does that work?

I’ve not tried the Voodoo3 yet, I need to pull it from another machine or find a 2nd for testing.

I don’t think the turbo trick is working for me as my Doom scores are still not great. I’ll try the switch on the FSB jumpers.

Edit: Booting at 33mhz with all three FSB jumpers in place then removing 1-2 and 5-6 after boot netted me a Doom score of 1033 realtics, much better. Is there a way to do it with only needing to change one jumper?

Checking my notes this m919 at 60x3 and 1024k cache is very close to the UUD at 50x4 and 256k cache. Although the UUD is by far the better board as feipoa has established. Still it’s fun to play around with this MEGACACHE! “Horns blaring”

Looks like i am spreading misinformation about the TURBO switch if both of you cannot replicate the automatic bus divider circumvention.
I thought this is how i made it work but maybe don't remember correctly and it was the FSB jumpers.

Best Quake 1 score at 180MHz Chadti99. Well job. : )

M919 works as advertised at up to 160MHz but gets fussy past that.
Biostar MB-8433uud-A is the better place overall. It really is the best assembly based on the UMC's UM8886/1 chipset.

There are few more 180/200 MHz capable 1Mb L2 cache 486 motherboards that will need examination at some point.
So far we went through
PCChips M918
PCChips M919
Chicony TK8880F / 2066A2
GA486AM/S
MSI-4144

Will be good to check as well and
DTK PKM-033S
FIC 486-PIO-3
Chaintech 486SPM or 486SOM
Soyo SY-4SA2
Soyo SY-030G or 4SA

Any other boards of that type that i cannot think of right now ?

Should I buy more 5x86 chips to find one that runs at 180 on air? Feeling rather left behind here with my lucky star 486E only running at 3x50MHz

maxtherabbit wrote on 2022-08-23, 18:36:

Should I buy more 5x86 chips to find one that runs at 180 on air? Feeling rather left behind here with my lucky star 486E only running at 3x50MHz

It’s worth a shot, you might get lucky early in your search or you might be 10-20 deep before you find one.

pshipkov wrote on 2022-08-23, 16:04:

Looks like i am spreading misinformation about the TURBO switch if both of you cannot replicate the automatic bus divider circum […]
Show full quote

Looks like i am spreading misinformation about the TURBO switch if both of you cannot replicate the automatic bus divider circumvention.
I thought this is how i made it work but maybe don't remember correctly and it was the FSB jumpers.

Best Quake 1 score at 180MHz Chadti99. Well job. : )

M919 works as advertised at up to 160MHz but gets fussy past that.
Biostar MB-8433uud-A is the better place overall. It really is the best assembly based on the UMC's UM8886/1 chipset.

There are few more 180/200 MHz capable 1Mb L2 cache 486 motherboards that will need examination at some point.
So far we went through
PCChips M918
PCChips M919
Chicony TK8880F / 2066A2
GA486AM/S
MSI-4144

Will be good to check as well and
DTK PKM-033S
FIC 486-PIO-3
Chaintech 486SPM or 486SOM
Soyo SY-4SA2
Soyo SY-030G or 4SA

Any other boards of that type that i cannot think of right now ?

Thanks! I couldn’t of done it without you guys. Def try a Samsung 32MB EDO module and I’m sure you’ll replicate my results.

This seems like a solid list, there is a bidding war on a 486SOM on eBay right now. Didn’t know it was sought after, are you guys accidentally bidding against each other on it 🤣? I can’t find any info that it accepts more than 512k though. It also has loads of those firecracker style tantalum caps.

Are there any Jetway boards that accept 1024k cache or are these rebrands of other motherboards?

I'm not bidding on anything and probably won't be for the rest of the year. I didn't see that listing. The boards looks neat; it is like the SPM but with a CR2032 holder, so perhaps it is the later design? I only have the SPM board which has been modified for the CR2032.