I sent you a PM regarding my dead TGUI9440-3

cj_reha, did you ever manage to upgrade the videocard to 2MB? I just upgraded my PCI bus tgui 9440 from 1MB to 2MB. Like in your case, sticking the RAM chips in the sockets didn't increase the reported memory. However on my card there's a marking on the PCB: 'R25 MD1 Reserved'. R25 was populated. Removing the resistor enabled the other 1MB on the card. Both the power-on screen and aida report 2MB now. Here's a pic of an example card with 2MB RAM, the same marking AND R25 left unpopulated. http://www.vgamuseum.info/images/zaatharen/tr … GUI9440_fhq.jpg

robbiesz wrote:

cj_reha, did you ever manage to upgrade the videocard to 2MB? I just upgraded my PCI bus tgui 9440 from 1MB to 2MB. Like in your case, sticking the RAM chips in the sockets didn't increase the reported memory. However on my card there's a marking on the PCB: 'R25 MD1 Reserved'. R25 was populated. Removing the resistor enabled the other 1MB on the card. Both the power-on screen and aida report 2MB now. Here's a pic of an example card with 2MB RAM, the same marking AND R25 left unpopulated. http://www.vgamuseum.info/images/zaatharen/tr … GUI9440_fhq.jpg

What happened to C27 there though? 😀
Seems like there was a tantalum cap there that blew out.

Haha, minor detail. 😀 Mine has it still.

In my case, I used two Siemens HYB51417bj-70, taking care to match the speed of the other ram chips on board, or lower. Mine has 70ns chips.
There are multiple chips that will work, they must match the specification, e.g. 256k×16 DRAM FPM 60ns. The socket is SOJ-40.
Take care that there are both EDO and FPM ram used across different TGUI-9440 models, and you need to match the type of the ram chip on board.

What kind of ram would this card take?

The existing chips are 256x4 Fast Page NN514256J-60, but the expansion slots are dip 24.

Would it take 512x4 ?

douglar wrote on 2024-02-02, 14:45:

What kind of ram would this card take? […]
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What kind of ram would this card take?

Photo Feb 02 2024, 9 40 17 AM.jpg

The existing chips are 256x4 Fast Page NN514256J-60, but the expansion slots are dip 24.

Would it take 512x4 ?

Nope. 256kx8

When you have done the upgrade, please make a posting in this thread:
Re: Vesa Local Bus graphics card - upgrade video memory
to confirm that the upgrade was in vain.

CoffeeOne wrote on 2024-02-02, 17:36:

Nope. 256kx8 […]
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Nope. 256kx8

When you have done the upgrade, please make a posting in this thread:
Re: Vesa Local Bus graphics card - upgrade video memory
to confirm that the upgrade was in vain.

Thanks for the info. Will do!

Edit: looks like finding 24pin DRAM isn't as straightforward as I thought and SOJ to DIP adapters look like a challenge.

Is it possible to stack 256Kx4 DIP20 to make 256Kx8 DIP24?

douglar wrote on 2024-02-02, 18:35:

Is it possible to stack 256Kx4 DIP20 to make 256Kx8 DIP24?

Yeah, that should work perfectly fine. Connect all pins except the data pins (address, /RAS, /CAS, /WE) on both chips. Then just use the 8 data bits provided by the 2 chips as the 8 data bits for the x8 chips. I didn't check pinouts, but it's likely that you mostly need to deal with the data pins and the GND pin.

douglar wrote on 2024-02-02, 18:35:

Thanks for the info. Will do! […]
Show full quote

CoffeeOne wrote on 2024-02-02, 17:36:

Nope. 256kx8 […]
Show full quote

Nope. 256kx8

When you have done the upgrade, please make a posting in this thread:
Re: Vesa Local Bus graphics card - upgrade video memory
to confirm that the upgrade was in vain.

Thanks for the info. Will do!

Edit: looks like finding 24pin DRAM isn't as straightforward as I thought and SOJ to DIP adapters look like a challenge.

Is it possible to stack 256Kx4 DIP20 to make 256Kx8 DIP24?

Many W32 PCI cards use V53C8256HP45 chips. But they seem to be hard to get, and if so expensive.

mkarcher wrote on 2024-02-03, 09:44:

Yeah, that should work perfectly fine. Connect all pins except the data pins (address, /RAS, /CAS, /WE) on both chips. Then just use the 8 data bits provided by the 2 chips as the 8 data bits for the x8 chips. I didn't check pinouts, but it's likely that you mostly need to deal with the data pins and the GND pin.

Thanks for the info. I'd have liked to do that if I had more time and if I hadn't been able to come across the 4 chips i needed to upgrade the board. It all identified fine, but I was having trouble getting things to sync at resolutions higher than 800x600x256 through my KVM switch. 1024x768x256 was coming in @ 85hz and 1024x768x64k @ 44. I'll do a clean win98 install and haul out yea ol' multisync for a test later this week.