I have that board in my 386, with the same ULSI 387 and 20MB RAM. 64KByte SRAMs are physically larger so they will not fit the sockets but with mods it would be possible to have up to 512KB cache (I have seen industrial boards with the chipset that have 512KB cache). Now if pinout could be located it shouldn't take too much effort to boost cache. That chipset is also supposed to support PCI and VLB too.

does cache make a huge difference in performance? because i only have 128kb in both my 386 + 486

chrisNova777 wrote:

does cache make a huge difference in performance? because i only have 128kb in both my 386 + 486

Doubling the cache can get you around 3-5% increase in performance. It pretty much depends on the app used.

Tiido wrote:

I have that board in my 386, with the same ULSI 387 and 20MB RAM. 64KByte SRAMs are physically larger so they will not fit the sockets but with mods it would be possible to have up to 512KB cache (I have seen industrial boards with the chipset that have 512KB cache). Now if pinout could be located it shouldn't take too much effort to boost cache. That chipset is also supposed to support PCI and VLB too.

512kb cache is incredibly rare on 386 motherboards. Usually the chipsets that support that much are the hybrid type and will only support 512kb when a true 486 CPU is installed. The closest I can think of at the moment is that Alaris Cougar motherboard that reportedly works with 512kb with a 486BL3 (386 type).

I've been looking for an Alaris Cougar for ages. That is for SURE on my wish list. I've heard amazing things about the 486BL3. It has VLB too.

I saw one on ebay the other day for around $100.

https://www.ebay.com/itm/Alaris-Cougar-II-Mot … =p2047675.l2557

Aw dang, it's over already.

chrisNova777 wrote:

does cache make a huge difference in performance? because i only have 128kb in both my 386 + 486

128k should be plenty on the 386. Unless *really* want the extra 1% performance boost you’d get from upgrading to 256k or already have the cache chips, it’s really not worth the money. Going from no cache to 64k is a huge performance boost. Going from 64k to 128k gets you about a 5% boost. Going from 128k to 256k gets you an additional 1 to 2%. (*Typical results, some specific apps may benefit more, by not by a lot.)

Anonymous Coward wrote:

I saw one on ebay the other day for around $100.

https://www.ebay.com/itm/Alaris-Cougar-II-Mot … =p2047675.l2557

I see a funky blue ZIF. Do you think a board like that could use a PGA-168 SXL2 with the Cyrix FasMath?

Did some research on my Forex 386 board. Apparently Forex 46C521 is 486 VLB chipset too.

feipoa wrote:

Anonymous Coward wrote:

I saw one on ebay the other day for around $100.

https://www.ebay.com/itm/Alaris-Cougar-II-Mot … =p2047675.l2557

I see a funky blue ZIF. Do you think a board like that could use a PGA-168 SXL2 with the Cyrix FasMath?

Unlikely, but it wouldn’t hurt to check the user manual.

Finally here is the MR BIOS for the "OPTI 386WB" a.k.a Shuttle HOT-307.

Speedsys refuses to dump a BIOS without a working HDD in the system for some reason although it dumps the BIOS to its own the directory on the floppy... that's the reason for the delay.

I also made a new BIOS dump of the OPTI 391 i486 MR BIOS just in case something was wrong with the old one and replaced the file in the message two pages back. I will also post it here.

Both files are dumped with NSSI using a clean DOS 8 boot disk.

OPTI 391 i386 MR BIOS. From a working generic OPTI 391 "OPTI 386WB" motherboard.

OPTI 493 i486 MR BIOS. From a non working generic OPTI 493 "ST0486WB" motherboard. The BIOS (chip) works perfectly fine with the Shuttle HOT-403 OPTI 493 i486 motherboard I used for dumping the file.

Don't try these BIOS files unless you have a way to recover your old BIOS in case it dosn't work!!!

Edit

repaced BIOS files and some faulty information

/Edit

Skyscraper wrote:

Finally here is the MR BIOS for the "OPTI 386WB" a.k.a Shuttle HOT-307. […]
Show full quote

Finally here is the MR BIOS for the "OPTI 386WB" a.k.a Shuttle HOT-307.

Speedsys refuses to dump a BIOS without a working HDD in the system for some reason although it dumps the BIOS to its own the directory on the floppy... that's the reason for the delay.

I also made a new BIOS dump of the OPTI 391 i486 MR BIOS just in case something was wrong with the old one and replaced the file in the message two pages back. I will also post it here.

Both files are dumped with Speedsys using a clean DOS 8 boot disk. If for some reason Speedsys makes non functional dumps I will try to find a better utility.

OPTI 391 i386 MR BIOS. From a working generic OPTI 391 "OPTI 386WB" motherboard.

OPTI 391 MR BIOS i386 .rar

OPTI 391 i486 MR BIOS. From a non working generic OPTI 391 "ST0486WB" motherboard. The BIOS (chip) works perfectly fine with the Shuttle HOT-403 OPTI 391 i486 motherboard I used for dumping the file.

OPTI 391 MR BIOS i486.rar

As both motherboards seems to be reference design boards and they both have WB in the name I guess either WB dosn't stand for "Write Back" or more likely reference design OPTI 391 motherboards use a write back L2 caching scheme.

Don't try these BIOS files unless you have a way to recover your old BIOS in case it dosn't work!!!

Sweet, thanks! I’ll give this a try tonight and report back!

I did a quick search and I'm now pretty confident that the OPTI 391 chipset is "write back" L2 only so L2 caching scheme shouldn't affect BIOS compatibility between motherboards with this chipset as all boards should be "WB".

The "WT" version of the chipset seems to be called OPTI 381 as seen on this motherboard.

OPTI 381 386 "WT" motherboard. The picture is "stolen" from an Ebay auction. If you own this picture and want me to remove it just send me a message.

The board arrived safely! I will send pics soon!
Bottom line, all seems to be in order. The battery has leaked a minor amount and some traces are a bit blackened, but i removed the battery so no more can occur. Additionally, the seller ensured me this board was fully functional, so I'm not worried. This board has external battery support, so I'll just use one of those.
Should i bother with trying to scrub up the traces that were affected if the board works fine without it?

You should, corrosion will slowly destroy this traces.

Alright. How do?

My method: apply mild acid on the affected area. Vinegar is most convenient. Apply with syringe or cotton swab. You might see some foaming if the battery spill is still recent. Wash away the vinegar: isopropyl alcohol works wonders. You can use water if you leave the board to dry thoroughly. After it dries, gently scrap away the solder mask (lacquer) from the affected traces and check to see if they are broken or not. A multimeter is handy at this stage.
Hope it helps.

quicknick wrote:

My method: apply mild acid on the affected area. Vinegar is most convenient. Apply with syringe or cotton swab. You might see some foaming if the battery spill is still recent. Wash away the vinegar: isopropyl alcohol works wonders. You can use water if you leave the board to dry thoroughly. After it dries, gently scrap away the solder mask (lacquer) from the affected traces and check to see if they are broken or not. A multimeter is handy at this stage.
Hope it helps.

I only do step two if the board dosn't function properly. I use plenty of vinegar in step one and any discoloured parts under the solder mask not exposed to the vinagar isn't exposed to oxygen either so with the battery gone the plague shoudn't spread.

I only remove the solder mask if I find that I need to fix broken traces and even then only if it isn't more convenient to just add a bodge wire. Perhaps it's just me beeing lazy but so far I have not seen any corrosion speading after I have removed the battery and scrubbed the affected area with vinegar.

Indeed, i should have mentioned. The solder mask should only be scrapped when it is obvious that the battery goo has seeped under it (and it becomes discolored/brittle/scrapes away very easily).