Kamerat wrote:

Just had to try it, running the C3 "Nehemiah" on my SE440BX-2 right now. I'm using the P13 BIOS.

I'll be damned.. Very good news! Is that with the MS6905 Master Slotket? I have a similar 'coppermine allowing' BIOS in the SR440BX (P06), but it still would not boot with any C3.

Kamerat wrote:

Trying multipliers lower than 5,5 when running 66MHz FSB makes the system crash on the Azza board.

On the GA-6BXC the crash limit is around 250MHz or lower. When I am chanced I will check these low speeds on some of the other motherboards, and see how they fare.

gerwin wrote:

I'll be damned.. Very good news! Is that with the MS6905 Master Slotket? I have a similar 'coppermine allowing' BIOS in the SR440BX (P06), but it still would not boot with any C3.

Yes, it's printed VER:2 on the PCB and configured like this:

1J1   J2   J3   J4
21-2  NC   2-3  1-2
3
4For 1,5V, dont know if the motherboard goes lower:
5JV0  JV1  JV2  JV3  JV4
6NC   NC   2-3  NC   2-3

gerwin wrote:

On the GA-6BXC the crash limit is around 250MHz or lower. When I am chanced I will check these low speeds on some of the other motherboards, and see how they fare.

I did some more testing and I could select multiplier 4.5x, but not 4.0x and 5.0x when running 66MHz FSB on the Azza board. Looking forward to your results.

Today I tried to add 512MB and 768MB RAM to my Intel SE440BX-2 running my VIA C3 "Nehemiah". With 512MB system ran just fine but when I added another 256MB stick the system turned extremely slow both under Windows XP SP3 and Windows 98SE. Ran SPEEDSYS with both 512MB and 768MB and the results are identical except for detected RAM size, so it doesn't look like a cache problem. Also tried my Tualatin which ran just fine with 768MB.

Have any of you guys tried running the Nehemiah with more than 512MB on the i440BX or any other chipsets?

Edit: 640MB (128+256+256) seems to run fine BTW.

Caching limit?

gdjacobs wrote:

Caching limit?

I thought that at first, but then I tried 640MB replacing the last added 256MB stick with a 128MB one. Now I replaced the 128MB stick with another 256MB one and the system is now running at full speed with the Nehemiah.

Maybe there's some kind of really rare compatibility issue with that 256MB stick. 😜

What were your latency timings?

gdjacobs wrote:

Caching limit?

gdjacobs wrote:

What were your latency timings?

After some more testing I think maybe your right about the caching limit after all, when running over 512MB it somtimes feels fast and somtimes it slows down like hell (might be when the CPU accsesses the uncached area).

Kamerat wrote:

gdjacobs wrote:

Caching limit?

gdjacobs wrote:

What were your latency timings?

After some more testing I think maybe your right about the caching limit after all, when running over 512MB it somtimes feels fast and somtimes it slows down like hell (might be when the CPU accsesses the uncached area).

This is possible.

And just as a precaution: What's the memory chip configuration of the memory modules you're using? How many chips do which modules of which size have?

Tetrium wrote:

And just as a precaution: What's the memory chip configuration of the memory modules you're using? How many chips do which modules of which size have?

All my modules are double sided, even the 128MB, so 16 chips on each.

Kamerat wrote:

Tetrium wrote:

And just as a precaution: What's the memory chip configuration of the memory modules you're using? How many chips do which modules of which size have?

All my modules are double sided, even the 128MB, so 16 chips on each.

In that case I'd reckon the 3x256MB modules shouldn't pose a problem.

But iirc, the cacheable area of Slot 1 was determined by the CPU, so if it's the C3 causing the problems, you're basically stuck I guess.

But if it's for slowdown, it shouldn't really matter that much anyway (unless you wanted to run dual boot or something).

Iirc some older Pentium 2s cached up to 512MB and later ones cached a practically unlimited amount. But 512MB is already quite alright for a slowdown rig I guess?

So I have my Ezra and MS6905 V2.0 Slotket up and running, but I can't find a way to reclock my FSB down to 66 mhz as seems to be permitted by the PLL. I want to hit those low 386 speeds. Anybody have luck changing this in software, especially using SMB to do so.

The intel motherboard autodetects the CPU to fit with a 100MHz bus. See: SR440BX review on vogons
On the MS6905 slotket, the only Bus speed related jumper is for forcing a 100MHz bus request.

Three options:
1) Modify motherboard like I did.
2) Modify slotket to do the same (preferable)
(3) Theoretically you could find out which traces on the CPU control stock BUS speed, and cut or bridge these. etc. But way way harder then option 2)

gdjacobs wrote:

So I have my Ezra and MS6905 V2.0 Slotket up and running, but I can't find a way to reclock my FSB down to 66 mhz as seems to be permitted by the PLL. I want to hit those low 386 speeds. Anybody have luck changing this in software, especially using SMB to do so.

Did some investigation after I read your post. The pin on J1 closest to the PGA370 socket is connected to B21 on the slot connector. Ground this pin and leave J1 and J4 without jumpers.

This got me 66MHz FSB with my Samuel 2 650/MS6905 combo on the SE440BX-2. 😎

Edit: If you need a ground point you can use pin number 3 on J4.

Thanks! That worked perfectly. I hit a lower limit of about 11 in Speedsys.

I'm not sure what further options are available. The SE440BX-2 is solid, but really lacks in memory tweaking options. Anyone have any other ideas?

Nice to hear. 😀

You can always use PCISET under DOS to change the PCI registers that contol the timings of the RAM. One other and more permanent option would be changing the timings in the SPD chip on the DIMM.

On the fly?

Yes, you also have WPCREDIT if you want to do the same in Windows. There's also a dedicated program for changing timings on the BX chipset in Windows, WBXTUNE, unfortunately it doesn't work with the C3.

Do these VIA cpu's run on i815e chipset ?

Official support are lacking, don't have any i815e boards myself but tried both a Nehemiah and a Samuel 2 in an i810 board (GA-6WMM7 rev. 2.0) without succsess. Have only tried my Ezra on the SE440BX-2 and it's working.

Kamerat wrote:

Nice to hear. 😀

You can always use PCISET under DOS to change the PCI registers that contol the timings of the RAM. One other and more permanent option would be changing the timings in the SPD chip on the DIMM.

Okay, so looking at the 440bx specification, DRAM timing data is on register 58h. The way I read it, I would OR the contents of that register with 3h or 0h and write to the register to add or remove additional CAS and RAS wait states. Sound correct?

Edit:
Wait states are on by default (3h is set). Looking at register 77:76, I'm hoping to change from CAS 2 to CAS 3 timings. I try altering bit 2 by inputing

1pciset 7190 8086 76 00000100 00000000

The response, in German, is:

1before :   76h: 000.0111

and the computer hard locks.

I've tried specifying hex for the mask and value, but that doesn't seem to be accepted by the utility as nothing is changed.

Known issue? Any workarounds?