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First post, by Nexxen

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I had this board for a while, had to replace the VGA connector because it just stripped away when removing the cable.

BIOS + Pics
American Megatrends 07/15/97
Was wondering if anyone had the latest Bios version.

Does anyone have a version with SDRAM? Any idea of the chip I could try to solder there?

Recap if you don't want to read the whole thing:

Supported cpus:
PIII :Coppermine up to max (tested), no Tualatin;
C3: up to Samuel2 core (all tested worked).
Celeron: Mendocino (333 to 533) + Coppermine (up to max, 1100)

About the SDRAM sockets:

they come unpopulatated (TSOP-II 86 pins) and you can only use "shared" memory for the onboard TNT2; max 32MB.

If soldered, the two SDRAM chips are recognized and used, but in BIOS shared memory must be set to "none" (0 MB) to work.
Local buffer memory used shows at POST.

I couldn't make 3D tests because I failed soldering the two chips and many traces got damaged, but it does work.
Micro soldering is difficult, you need a microscope and good skill, also the working area isn't very large.
I was partially successful with 16 MB, but I think that 32 is feasible.

Video ram speed depends heavily on Bus speed.

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Last edited by Nexxen on 2022-10-16, 20:54. Edited 5 times in total.

PC#1 Pentium 233 MMX - 98SE
PC#2 PIII-1Ghz - 98SE/W2K

Reply 1 of 58, by Nexxen

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Found the manual!

Reading this I presume I can solder 32MB of sdram to have a max of dedicated ram for the graphics card alone, not sharing with main.
Gonna try that.

Probably PC-133 should work great as the GFXPro ( chip comes with a PC133 writing on it.
😀

Goes as Amptron 3754

Edit, it'd at https://theretroweb.com/motherboards/s/pcchip … -plus#downloads

Last edited by Nexxen on 2022-10-15, 16:30. Edited 1 time in total.

PC#1 Pentium 233 MMX - 98SE
PC#2 PIII-1Ghz - 98SE/W2K

Reply 2 of 58, by Nexxen

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2M*32 makes 2x8MB chips.

I have to take 2 from a 64MB ram module.

Question is: are they gonna get detected?
Guessing no modules are detected it goes to shared ram, if present no sharing.

PC#1 Pentium 233 MMX - 98SE
PC#2 PIII-1Ghz - 98SE/W2K

Reply 3 of 58, by majestyk

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The 32MB video RAM refer to to the shared main-memory here, I´m afraid.

video_ram1.JPG
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You can populate 1GB main memory, the onboard graphics will grab 32MB of it as shared memory. This is just a tiny bit of 1GB.
I think it´s not worth the effort populating the two RAM chips onboard for an additional 16MB of dedicated video-RAM just to free 16MB of main memory, except if it would run at a higher speed than main memory - which doesn´t seem to be the case here if your maximum FSB is 133 MHz or, if the 16MB onboard RAM would add to the 32MB shared RAM for a total of 48MB. Not sure if the (ALi Pro 4?) Northbridge will do that or if it´s limited to 32MB total memory...

Reply 4 of 58, by Nexxen

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majestyk wrote on 2022-10-13, 06:36:
The 32MB video RAM refer to to the shared main-memory here, I´m afraid. […]
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The 32MB video RAM refer to to the shared main-memory here, I´m afraid.

video_ram1.JPG

You can populate 1GB main memory, the onboard graphics will grab 32MB of it as shared memory. This is just a tiny bit of 1GB.
I think it´s not worth the effort populating the two RAM chips onboard for an additional 16MB of dedicated video-RAM just to free 16MB of main memory, except if it would run at a higher speed than main memory - which doesn´t seem to be the case here if your maximum FSB is 133 MHz or, if the 16MB onboard RAM would add to the 32MB shared RAM for a total of 48MB. Not sure if the (ALi Pro 4?) Northbridge will do that or if it´s limited to 32MB total memory...

To my knowledge dedicated memory is better than shared.
I'm not losing anything if it doesn't work 😀

A new little story to tell on a winter night. All the circuitry is there, I think it's safe to assume that they just didn't bother installing the chips.
I put it in my to-do list. Not happening any time soon, but I after sleeping on it, why not?

I guess I'll have to do benchmarks first without and after soldering.

PC#1 Pentium 233 MMX - 98SE
PC#2 PIII-1Ghz - 98SE/W2K

Reply 5 of 58, by dionb

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majestyk wrote on 2022-10-13, 06:36:
The 32MB video RAM refer to to the shared main-memory here, I´m afraid. […]
Show full quote

The 32MB video RAM refer to to the shared main-memory here, I´m afraid.

video_ram1.JPG

You can populate 1GB main memory, the onboard graphics will grab 32MB of it as shared memory. This is just a tiny bit of 1GB.
I think it´s not worth the effort populating the two RAM chips onboard for an additional 16MB of dedicated video-RAM just to free 16MB of main memory, except if it would run at a higher speed than main memory - which doesn´t seem to be the case here if your maximum FSB is 133 MHz or, if the 16MB onboard RAM would add to the 32MB shared RAM for a total of 48MB. Not sure if the (ALi Pro 4?) Northbridge will do that or if it´s limited to 32MB total memory...

Not ALi, this is a SiS 630 board.

The issue with integrated VGA with UMA architecture isn't the memory bandwidth for VGA core on its own, it's the fact it's shared with CPU bandwidth, so as soon as both are stressed (i.e. as in pretty much any game), they compete for it and are both castrated by the bottleneck. So adding *anything* for the VGA core to stop it competing for the same bandwidth as CPU makes eminent sense.

Now, whether you can get this to work (hardware + BIOS support) is another matter entirely, but given how totally crap the board is otherwise, if you're decent at SMD soldering, I'd say it's worth the risk.

Reply 6 of 58, by Nexxen

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dionb wrote on 2022-10-13, 10:57:
Not ALi, this is a SiS 630 board. […]
Show full quote
majestyk wrote on 2022-10-13, 06:36:
The 32MB video RAM refer to to the shared main-memory here, I´m afraid. […]
Show full quote

The 32MB video RAM refer to to the shared main-memory here, I´m afraid.

video_ram1.JPG

You can populate 1GB main memory, the onboard graphics will grab 32MB of it as shared memory. This is just a tiny bit of 1GB.
I think it´s not worth the effort populating the two RAM chips onboard for an additional 16MB of dedicated video-RAM just to free 16MB of main memory, except if it would run at a higher speed than main memory - which doesn´t seem to be the case here if your maximum FSB is 133 MHz or, if the 16MB onboard RAM would add to the 32MB shared RAM for a total of 48MB. Not sure if the (ALi Pro 4?) Northbridge will do that or if it´s limited to 32MB total memory...

Not ALi, this is a SiS 630 board.

The issue with integrated VGA with UMA architecture isn't the memory bandwidth for VGA core on its own, it's the fact it's shared with CPU bandwidth, so as soon as both are stressed (i.e. as in pretty much any game), they compete for it and are both castrated by the bottleneck. So adding *anything* for the VGA core to stop it competing for the same bandwidth as CPU makes eminent sense.

Now, whether you can get this to work (hardware + BIOS support) is another matter entirely, but given how totally crap the board is otherwise, if you're decent at SMD soldering, I'd say it's worth the risk.

Do you think that getting those out any RAM stick should be ok?
I thought doing 8+8 and 16+16.

Being total crap I'm going to try both. PC-133 looks fine to me, probably going to test 16+16 first, may just gonna cut down to 8+8.
PC Chips, the wonder that never ends 😀

PC#1 Pentium 233 MMX - 98SE
PC#2 PIII-1Ghz - 98SE/W2K

Reply 7 of 58, by majestyk

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dionb wrote on 2022-10-13, 10:57:

Not ALi, this is a SiS 630 board.

Are you sure? According to this site the "GFX Pro" (as PC-Chips relebeled it) is in fact an "ALi M1631" chipset:

https://hardwaresecrets.com/chipset-aliases-t … -vx-pro-and-co/

(I always found the infos collected there to be 100% accurate!)

The manual also states:

wxga1a.JPG
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I can´t imagine that ancient WXGA resolution @ 16bit colour and 60 Hz could max out the PC133 SD-RAM bandwith or restrict CPU memory access too much. Of course this depends on the chipset / MCH again.
Maybe someone has the relevant data available.

Reply 9 of 58, by Nemo1985

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I had this board, I can clearly remember that the memory bandwidth was severy crippled. Mine didn't have the memory chips on the board too.
It suddenly stopped working from a day to another I did some tests but I wasn't able to make it work again so I trashed it.

Reply 11 of 58, by Nexxen

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Nemo1985 wrote on 2022-10-13, 23:33:

I had this board, I can clearly remember that the memory bandwidth was severy crippled. Mine didn't have the memory chips on the board too.
It suddenly stopped working from a day to another I did some tests but I wasn't able to make it work again so I trashed it.

Do you still have the Drivers cd?

PC#1 Pentium 233 MMX - 98SE
PC#2 PIII-1Ghz - 98SE/W2K

Reply 12 of 58, by Nemo1985

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Nexxen wrote on 2022-10-14, 04:33:
Nemo1985 wrote on 2022-10-13, 23:33:

I had this board, I can clearly remember that the memory bandwidth was severy crippled. Mine didn't have the memory chips on the board too.
It suddenly stopped working from a day to another I did some tests but I wasn't able to make it work again so I trashed it.

Do you still have the Drivers cd?

never had any cd but I didn't have problem to find the drivers even for the weird integrated vga

Reply 18 of 58, by Nexxen

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majestyk wrote on 2022-10-15, 18:49:

Are there any known mainboards with this very chipset that take advantage of onboard dedicated memory at all?

No idea.
Will go on and see.

Can't make 3DMark99 work. Asks for DX6 compatible video card and won't go further than error message.

Any other program to test this video card?

PC#1 Pentium 233 MMX - 98SE
PC#2 PIII-1Ghz - 98SE/W2K

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