Um, weird. Searching that VER:1.0r01 WB1 string brings up conflicting info by itself.

However, going through my A-Trend BIOS stash and reading them in a BIOS editor, the date on that screenshot seems to match the ATC6240M v3 BIOS version 3.0r02. It seems your board is actually an ATC6420M V3: PCB rev R06, despite the PCB silk printing. But I need the BIOS ID located on the bottom left screen area on POST to confirm before going any further.

It should presumably match this:
BIOS info: 01/09/2000-i440BX-W977-62400000C-EC

The BIOS message is informational only.
BIOS message: 6240 VER:3.0r02 WB1

Also, A-Trend was placing stickers over the board revision silkscreen with the revision they made depending on the design, and yours may be missing that sticker. (ATC6240M v2: PCB rev R05, ATC6240M V3: PCB rev R06, and ATC6420V-01 use the same PCB layout, hence the confusion.)

Edit: newer post corrects the mainboard PCB differences.

I have also this kind of motherboard.

My Atrend board is called: ATC6240 without anything.
Its a gold kind of board v2. Because its Intel 440BX it should be ATC6240M

AmiSapphire wrote on 2021-09-28, 15:52:

It should presumably match this:
BIOS info: 01/09/2000-i440BX-W977-62400000C-EC

Sure enough, it does say "i440BX-W977-62400000C-EC" on post. Since it does say that do you believe flashing it with a bios for a "ATC6240M V3: PCB rev R06" would work rather than brick it?

Thank you for pointing me in the right direction. Also thank you for the information about A-trend in general. It totally makes sense they would use reuse boards and use stickers to cover up model numbers.

Downer wrote on 2021-09-29, 13:01:

AmiSapphire wrote on 2021-09-28, 15:52:

It should presumably match this:
BIOS info: 01/09/2000-i440BX-W977-62400000C-EC

Sure enough, it does say "i440BX-W977-62400000C-EC" on post. Since it does say that do you believe flashing it with a bios for a "ATC6240M V3: PCB rev R06" would work rather than brick it?

Thank you for pointing me in the right direction. Also thank you for the information about A-trend in general. It totally makes sense they would use reuse boards and use stickers to cover up model numbers.

That string does point to that particular version board, though I would come up with a backup plan in any case something goes wrong.
BIOS updates are located here: http://www.win3x.org/uh19/motherboards/7078

ATC-6240BX BIOS Released Note.doc: with the only BIOS note for rev R06 preserved.

ATC-6240 BX

This BIOS version 3.0r05 support for :
1. new Celeron ( so far 766 MHZ above )
2. Pentium III ( Coppermine ) up to 850 MHZ .
3. implement Win ME & Win 2000 Hibernate feature .
4. VIA Cyrix III CPU

--

Also I JUST noticed this note on the page I linked:

"backside of the motherboard near the DIMM slots gives PCB rev, only R06 has Coppermine support"

I wonder if it says some form of "R06" on the bottom of the board? No one person would normally think to take a photo of the bottom side of the board. However, I checked my own Atrend 6240M board, and sure enough, "391-6355-C00R03" was printed on the silkscreen. So mine is a rev R03 board. My board is a green color, however.

--

I'll also have to correct my own statement on the board layout, as I just have run into a picture of a gold version of the ATC-6240 with the earlier board layout that 6240M R01-R03 and 6240V-00 uses, possibly rev R05. (Ironically, they were adding stickers on those boards for the ATC-6240v-00.) So, only ATC-6240M V3: rev R06 and ATC-6240V-01 use the same board layout. Insane. The 6240M v2 board entry will need a photo change on win3x/Ultimate Hardware 2019, as it is the wrong photo for it.

It also seems I will have to update my own ATC-6240 page with this info.

AmiSapphire wrote on 2021-09-29, 15:43:

That string does point to that particular version board, though I would come up with a backup plan in any case something goes wr […]
Show full quote

Downer wrote on 2021-09-29, 13:01:

AmiSapphire wrote on 2021-09-28, 15:52:

It should presumably match this:
BIOS info: 01/09/2000-i440BX-W977-62400000C-EC

Sure enough, it does say "i440BX-W977-62400000C-EC" on post. Since it does say that do you believe flashing it with a bios for a "ATC6240M V3: PCB rev R06" would work rather than brick it?

Thank you for pointing me in the right direction. Also thank you for the information about A-trend in general. It totally makes sense they would use reuse boards and use stickers to cover up model numbers.

That string does point to that particular version board, though I would come up with a backup plan in any case something goes wrong.
BIOS updates are located here: http://www.win3x.org/uh19/motherboards/7078

ATC-6240BX BIOS Released Note.doc: with the only BIOS note for rev R06 preserved.

ATC-6240 BX

This BIOS version 3.0r05 support for :
1. new Celeron ( so far 766 MHZ above )
2. Pentium III ( Coppermine ) up to 850 MHZ .
3. implement Win ME & Win 2000 Hibernate feature .
4. VIA Cyrix III CPU

--

Also I JUST noticed this note on the page I linked:

"backside of the motherboard near the DIMM slots gives PCB rev, only R06 has Coppermine support"

I wonder if it says some form of "R06" on the bottom of the board? No one person would normally think to take a photo of the bottom side of the board. However, I checked my own Atrend 6240M board, and sure enough, "391-6355-C00R03" was printed on the silkscreen. So mine is a rev R03 board. My board is a green color, however.

--

I'll also have to correct my own statement on the board layout, as I just have run into a picture of a gold version of the ATC-6240 with the earlier board layout that 6240M R01-R03 and 6240V-00 uses, possibly rev R05. (Ironically, they were adding stickers on those boards for the ATC-6240v-00.) So, only ATC-6240M V3: rev R06 and ATC-6240V-01 use the same board layout. Insane. The 6240M v2 board entry will need a photo change on win3x/Ultimate Hardware 2019, as it is the wrong photo for it.

It also seems I will have to update my own ATC-6240 page with this info.

I just took apart the PC, removed the motherboard and it did have "391-6355-C00R06" behind the Dimm slots.

So even after updating the bios to "3.0r05 " the motherboard may still see the SL4KL at post incorrectly since it still is not technically supported. Hmm I may just have to risk it and see.

My 440bx doesnt recognise my 1.1GHz coppermine celeron properly at POST - it doesn't matter, it runs fine and correct speed is confirmed with both softfsb and cpuz

It worked! The latest bios now reads the CPU correctly at post. Thank you again for pointing me in the right direction.

^ You're welcome. Now that I know that BIOS 3.0r05 unofficially supports 1GHz Intel Coppermine CPUs that use the 100MHz bus speed, that note has just been added to my A-trend ATC-6240 page.

The 6240M v2 board entry will need a photo change on win3x/Ultimate Hardware 2019, as it is the wrong photo for it.

Done

VIA manuals have been replaced by the 6240/6240M manual. Picture of your board has been added with credits link to your website. If you have additional stuff, just post away. Email is fine too.