Just about all 40MHz boards had cache. I personally think getting on without cache would be a mistake, especially since getting one with cache is not really expensive or difficult.

Are you certain the board has no cache? If it uses the MX chipset, it has an 8kb integrated cache that is roughly equal to having 64kb of external cache.

Anonymous Coward wrote on 2020-06-06, 15:08:

Just about all 40MHz boards had cache. I personally think getting on without cache would be a mistake, especially since getting one with cache is not really expensive or difficult.

Are you certain the board has no cache? If it uses the MX chipset, it has an 8kb integrated cache that is roughly equal to having 64kb of external cache.

It is a MX83C306AFC/305AFC chipsets board and I didn't see any sockets or similar cache but now I understand why. Interesting, are there any benchmark results for comparison with other chipsets with cache?

At first I was hoping to find one of the latest with socket for both cpu and fpu and cache but prices seems to be not so low, often untested. Also with the soldered DX40 I was worried that it may fail sometime in the future and the whole mainboard would be useless while with the socket I'd also have the Cyrix alternative. 🙁

Meanwhile I've also seen a ALi 1429 chipset based one that it'd need only the battery change. Would it be a better mainboard/chipset? But these one would cost three times the first...

The ALi1429 was a hybrid 386/486 chipset. It's pretty advanced for a 386. I owned one some time ago, and it was definitely not slow. Most of the small formfactor 386DX boards are roughly the same speed. You will only see small performance benefits by nitpicking about your board (I like to nitpick).

If you don't want to change the CPU, there is definitely nothing wrong with a surface mount 386. The 386 boards from 1993+ were super reliable and really hard to kill. Even if it got bad solder joints, you could still repair it with the right tools.

I wonder if the MX board you are looking at is an Octek Jaguar V. That was a pretty common board, and somewhat decent. I believe there is a thread with speedsys benchmarks that has an MX board in there somewhere. The results seemed normal for a 386. However, I don't know how much memory those MX boards can cache. If you just want 8MB it's totally fine.

Post your 386 Speedsys results here

It's not that mainboard, it has a E117895 code on the back, there're the solder points for the cpu socket but not installed (only fpu socket is there) and under the simm socket there're both the cpu and the chipsets. Four simm slots. The usual Amibios 386DX bios.

Does the ALi ones support the Cyrix 486DLC cpu?

I would imagine pretty much any 386 board with an ALi1429 should support DLC chips, though that also depends on the PCB layout and the BIOS programming.

Anonymous Coward wrote on 2020-06-06, 16:26:

I would imagine pretty much any 386 board with an ALi1429 should support DLC chips, though that also depends on the PCB layout and the BIOS programming.

Thanks for the answers. I really like the ALi chipset board for the sockets expandibility and the cache. Four cache slots would arrive to 256kbytes of it?
My GD-5429 1MB DRAM ISA card ask to be used in msdos games.. 😁

Nope. Four 28-pin cache sockets will get you 128kb cache, which is a lot for a 386.

Anonymous Coward wrote on 2020-06-07, 00:21:

Nope. Four 28-pin cache sockets will get you 128kb cache, which is a lot for a 386.

Thanks. I was also considering another mobo, an UMC based with the DX40 soldered, cache sockets but also with two "cpu/fpu" sockets that both seems similar; one has 14-pins of height the other one less but it's not like the usual FPU socket with only two vertical pins columns but both has three (outside the empty center socket point). Are these still 386 and 387 sockets?

Yes. The two centre rows will accept a standard 387. The outer rows are used by Weitek 3167 and Cyrix EMC. Both of those are more or less useless unless you plan on doing CAD.

Anonymous Coward wrote on 2020-06-07, 09:53:

Yes. The two centre rows will accept a standard 387. The outer rows are used by Weitek 3167 and Cyrix EMC. Both of those are more or less useless unless you plan on doing CAD.

Good, I cannot say which model the mainboard is but I asked for it but I'm sure it's a UMC based one probably manufactured around 1992. I'd expect to have a jumper to select the socket cpu or the soldered one? Anyway it has an "MG" word written on the pcb and assembled in usa. Sure has the DX-40 and already four of eight cache sockets installed. Strangely the remaining empty cache sockets seems installed far from the others and each one on the right vertical side of the pcb while the four ones already installed all the in the above right corner. Still if I have to ask the owner for Cyrix compatibility and I've to find a good case for it. I want to find one as compact as possible horizontal with the led freq hole.. too bad I already had a similar case in the past and trashed it.. 🙁

I like 386 boards from 1992. By that time they had worked out pretty much all of the bugs, but they hadn't yet started cost cutting. 1992 boards also have a chance of being Cyrix compatible since the DLC came out that year...but even for the boards that don't they probably support hidden refresh so you can still run the Cyrix in BARB mode.

Whether or not there is a jumper to disable the onboard CPU is anyone's guess. I've had a lot of boards like that where you just had to desolder the onboard CPU if you wanted to use the socket.

UMC 386 chipsets seem to be pretty good. It's probably a UM480 chipset, in which case I highly recommend switching to MR-BIOS.

Anonymous Coward wrote on 2020-06-07, 13:45:

I like 386 boards from 1992. By that time they had worked out pretty much all of the bugs, but they hadn't yet started cost cutting. 1992 boards also have a chance of being Cyrix compatible since the DLC came out that year...but even for the boards that don't they probably support hidden refresh so you can still run the Cyrix in BARB mode.

Whether or not there is a jumper to disable the onboard CPU is anyone's guess. I've had a lot of boards like that where you just had to desolder the onboard CPU if you wanted to use the socket.

UMC 386 chipsets seem to be pretty good. It's probably a UM480 chipset, in which case I highly recommend switching to MR-BIOS.

The board is a MG-38606 the chipset is UM82C481AF. I'm looking for a manual but I can't find it! The board has still good traces while some under the battery has been previously uncovered a bit to check their integrity, does some specific "paint" exist to recover it like a pcb-layer? EDIT: I've found those green UV protective paint they call "solder mask" in 10 cc quantity. Are those right?
I think I'll buy it. But I'm not sure what would happen if I'd use the socket while the cpu is still soldered, may I damage the board?

The board is exactly like this one found online:

I had a 386 board years ago that had a soldered dx-40 and a socket and if you inserted a cpu it automatically disabled the on board one.

chrismeyer6 wrote on 2020-06-07, 18:43:

I had a 386 board years ago that had a soldered dx-40 and a socket and if you inserted a cpu it automatically disabled the on board one.

Thanks. I still try to look for the manual to see if it's (I suppose it should be) factory designed that way even this board.

Anonymous Coward wrote on 2020-06-06, 15:08:

Are you certain the board has no cache? If it uses the MX chipset, it has an 8kb integrated cache that is roughly equal to having 64kb of external cache.

I am wondering about this. Is this really equal to 64kB cache? With only 8k, not even a fully-associative cache would have been that efficient.

I need to get one of this to see this in action...

I'm also buying a period correct 540MB hard disk cause I really like to have the usual classic sound of loud disks. 😁

chrismeyer6 wrote on 2020-06-07, 18:43:

I had a 386 board years ago that had a soldered dx-40 and a socket and if you inserted a cpu it automatically disabled the on board one.

What mobo was that, do you remember? Because all the ones I've seen require a jumper to be moved to disable the on-board 386.

I lost that poor system to a flood about 8 years ago and I can't remember which board it was. I just remember it was from Zeos and it was the original motherboard from when we bought it.

From what I have heard, you can use clear nail polish to cover up exposed PCB traces.