TheRetroWeb has it.

Apart from retroweb, I did not find any confirmation that the ATC-6400 is the same board. The manual does not say anything about the JP11 connector and says that the board only supports Pentium II.
The board correctly recognizes the Pentium III Katmai 550. The Coppermine on modded PPGA adapter also works, but it does not start after changing the FSB from 66 to 100.

"ATC-6400" is even printed on the white sticker at the bottom.

Hope you replaced the leaky cap...

dulu wrote on 2024-07-21, 23:29:

Dual processor systems have always been outside of my scope of interest, so I didn't know much about xeon slot II processors. However, this mobo allows for a close comparison of xeon vs pentium processors in games under Win98, and theoretically creating a period-correct system that will outperform the highest PII / PIII models (without leaving the second slot unused). Since few people have such an opportunity, I feel obliged to create such a test : )

You write "Dual processor systems". I would not expect this board to run with both a PII AND a Xeon at the same time?

dulu wrote on 2024-07-21, 23:29:

2: What is the JP11 connector next to northbridge for?

That looks like a connector for a thermistor (for measuring cpu temp)

dulu wrote on 2024-07-22, 09:27:

Apart from retroweb, I did not find any confirmation that the ATC-6400 is the same board. The manual does not say anything about the JP11 connector and says that the board only supports Pentium II.
The board correctly recognizes the Pentium III Katmai 550. The Coppermine on modded PPGA adapter also works, but it does not start after changing the FSB from 66 to 100.

Run Bios Patcher on it, see if that helps.

majestyk wrote on 2024-07-22, 09:55:

"ATC-6400" is even printed on the white sticker at the bottom.

Hope you replaced the leaky cap...

You`re right, what a shame..
Cap replaced, like i said 😀

H3nrik V! wrote on 2024-07-22, 10:39:

dulu wrote on 2024-07-21, 23:29:

Dual processor systems have always been outside of my scope of interest, so I didn't know much about xeon slot II processors. However, this mobo allows for a close comparison of xeon vs pentium processors in games under Win98, and theoretically creating a period-correct system that will outperform the highest PII / PIII models (without leaving the second slot unused). Since few people have such an opportunity, I feel obliged to create such a test : )

You write "Dual processor systems". I would not expect this board to run with both a PII AND a Xeon at the same time?

I meant that the board is designed to run a single Xeon, so it is better suited to a Win98-based system. I know that it won't support two processors at the same time 😀

These Freeway red PCBs are eye catching for sure.
Great for early P2 and P3 processors. Well packaged for that mission. But if you want more from them - they will struggle.
Here is a short overview of FW-6280BXDR, for reference. It answers some of your questions.
Usb mouse works in “later” windows/linux versions.
One issue with the 6280 version is the closely placed cpu slots. Prevents you from inserting a second CPU with standard height heatsink/fan. Requires finding low profile ones, which is more difficult nowadays than it sounds. Not great.
I think it is the same for your board, but since it does not allow dual cpu configuration - not a problem really.

The board model number "150" does not gurantee that it's 150 MHz.
There is no mention of "150MHz" or any other frequency in the text on the motherboard that directly corresponds to the model number "150".

FSB is controlled through the BIOS.
There are options for 150 and 155, at least in the 6280 model. They kind of work.
I assume it is similar for 6400.

kevin223 wrote on 2024-07-23, 14:40:

The board model number "150" does not gurantee that it's 150 MHz.
There is no mention of "150MHz" or any other frequency in the text on the motherboard that directly corresponds to the model number "150".

It's clearly listed on their spec sheet for the board...

I will start playing further only when I get the right xeon. After a long search, it seems that I will not find a matching retention bracket, no board has such a mounting. I'll have to create something.

In the meantime - does anyone know what board/graphics card this heatsink was mounted on? I remember well that it was on something that I moved to scrap. It must have been some riva tnt, i740, mx200 or something. I clearly remember that characteristic drilled hole in the corner.

Someone could say this is obvious, but it wasn’t obvious to me. A certain Japanese website mentions two versions of this motherboard — FW6400GX and FW6400GXR — and they are not the same.

• The FW6400GX has a green PCB, while the FW6400GXR has a red PCB (on red motherboard there is still 6400GX marking on silkscreen, which is misleading).
• The FW6400GXR is identical to the ATC-6400, and the BIOS from the ATC6400 works on the FW6400GXR (by the way, has anyone ever actually seen an ATC-6400?).
• All BIOS images on RetroWeb are for the green GX board, and flashing them onto a GXR will brick it.
• The non-working USB keyboard is a BIOS issue — flashing the ATC BIOS ROM or the GXR 129 ROM makes the keyboard work in the BIOS. I am attaching the GXR 129 ROM here, because it is hard to find; it’s not even available on the Internet Archive. The ROM for the ATC6400 is easy to find, but the FREEWAY logo disappears during POST.

ROM 129 is the newest version my friend managed to find. Below is an changelog. As you can see, there is an even newer BIOS that adds support for newer hard drives. There is also a mention of a manual file in Japanese; it appears that an English-language manual never existed. This manual could explain what the JP11 header is used for. It is not a thermistor connector — that role is served by the RT1 header.

By the way - looks like FSB150 works

Does your board have a Winbond/Nuvoton W83781D SIO chip? I wonder if my SIV utility will find it and report the temperatures, fan speeds and voltages, please will you try it and post the Menu->File->Save Local files? It should work on Windows 9x and Windows NT/2000/XP, in general SIV will report more on NT/2000/XP.

dulu wrote on 2024-07-30, 20:39:

I will start playing further only when I get the right xeon. After a long search, it seems that I will not find a matching reten […]
Show full quote

I will start playing further only when I get the right xeon. After a long search, it seems that I will not find a matching retention bracket, no board has such a mounting. I'll have to create something.

In the meantime - does anyone know what board/graphics card this heatsink was mounted on? I remember well that it was on something that I moved to scrap. It must have been some riva tnt, i740, mx200 or something. I clearly remember that characteristic drilled hole in the corner.

Although old - it's likely originating from a Voodoo Banshee made by Sparkle - SP3800 more exactly.

Where is menu/file/save as? i can`t find it. Temp report is correct, i have cable thermistor which i`m touching and i see that temp is changing.
Out of curiosity, why did you want me to check this? Is this chip uncommon?

dulu wrote on 2026-01-10, 13:35:

Where is menu/file/save as? i can`t find it.
Out of curiosity, why did you want me to check this?

The attached should show how to navigate to Menu->File->Save Local. I asked as it's an unusual motherboard, further in general if there is something unexpected on the screen shot the save files are likely to tell me why.

I just noticed the disk drive temperature is missing, did you get a pop-up window asking you to reboot to enable them?