VOGONS


First post, by BLockOUT

User metadata
Rank Member
Rank
Member

this motherboard is interesting

gigabyte 7zx
On revision 1 it came with an isa slot, and accepted athlon xp.
on revision 5 they took out the isa slot and also took out a cheap near it.

my question is, would it be possible to add an isa slot to the revision 5 ? or the chip is needed for making isa work?

7zx.jpg

Reply 1 of 14, by Nexxen

User metadata
Rank Oldbie
Rank
Oldbie

They probably removed components to cheap it down on price.

If you can find another motherboard to check differences, I'm pretty sure you can add the slot.
Some boards have all the related chips removed as well, making it difficult to have a functional i/o port or slot (smd resistances, capacitors...).

Giving for granted that you know how to solder.


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

Reply 2 of 14, by BitWrangler

User metadata
Rank l33t
Rank
l33t

My feel is that if it needed that chip for the ISA slot to work, it wasn't quite a fully compatible ISA slot. Unless you know for sure that every piece of hardware you want to use works on the revision 1, then I wouldn't bother pursuing it.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 3 of 14, by computerguy08

User metadata
Rank Member
Rank
Member

That chip is just a backup BIOS, Gigabyte dubbed it "DualBIOS".

You should be able to add an ISA slot, the resistor packs are there.
Same mod can be done to a 7ZXE.

EDIT: I was looking on the right side of the image, where you have another IC missing (that one is the 2nd BIOS 😜) ; only way to know is to try adding the slot and see if you have DMA and stuff.
EDIT 2: the VT82C686B should be able to do ISA by itself, without additional chips.

Looking for a motherboard? You can find it in Ultimate Retro: https://www.ultimateretro.net/motherboards/search
Join our Discord server here: https://discord.gg/HWWH7hsk2p

Reply 6 of 14, by dionb

User metadata
Rank l33t
Rank
l33t

Looking at the best pics of the r5.1 board I can find, there seems to be something written in the silksrceen where that chip would go. What does it say?

I find the CT5880 audio option plausible, as that's one of the other differences between the two revisions, and the design with an oscillator nearby looks a perfect fit. The 686B southbridge supports ISA natively, so no PCI-ISA bridge chip needed normally.

I wouldn't be concerned about the chip, I'd rather worry about SMD resistor networks. The pic seems to show some near the empty holes on the r5.1, but are they the same value as the r1.0 board? That's the question...

Then again, soldering an ISA slot is pretty basic and (even with my bad eyes and sloppy hands) risk-free. You could just slap it on and see what happens 😉

Reply 7 of 14, by Doornkaat

User metadata
Rank Oldbie
Rank
Oldbie

I have also added an ISA slot on two Gigabyte Slot A motherboards before. The slot was omitted in an OEM version along with the sound chip and second BIOS EEPROM, just like in OP's board. The south bridge contained the PCI-ISA bridge, all the passives were on the board and just soldering in the slot worked perfectly.
I say OP has a high chance of having the same result.👍 Go for it!😃

Reply 8 of 14, by Bruno128

User metadata
Rank Newbie
Rank
Newbie
BLockOUT wrote on 2021-09-14, 15:36:

or the chip is needed for making isa work?

Hi. This chip you are referring to has nothing to do with ISA slot.

Attachments

  • ct5880 ga7zx.png
    Filename
    ct5880 ga7zx.png
    File size
    331.04 KiB
    Views
    377 views
    File comment
    CT5880
    File license
    Public domain

Reply 10 of 14, by BitWrangler

User metadata
Rank l33t
Rank
l33t

It's a gigabyte, talk him down... 🤣 just kidding, had my beefs with gigabyte stuff in the past.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 11 of 14, by Robin4

User metadata
Rank l33t
Rank
l33t
BitWrangler wrote on 2021-09-14, 15:49:

My feel is that if it needed that chip for the ISA slot to work, it wasn't quite a fully compatible ISA slot. Unless you know for sure that every piece of hardware you want to use works on the revision 1, then I wouldn't bother pursuing it.

That chip could be an ISA to PCI bridge controller. On later boards they removed the normal ISA specs and connecting isa slot to the PCI bus with use of these ISA to PCI bridge controllers.

~ At least it can do black and white~

Reply 12 of 14, by BitWrangler

User metadata
Rank l33t
Rank
l33t

That was my first thought but others seem to have convincing info that it's the audio controller and the chipset handles ISA native.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 13 of 14, by BLockOUT

User metadata
Rank Member
Rank
Member

just came back with it, the board is beautiful like new, just a bit of dust in it. it came with the original amd cooler, 15gb hard drive and a floppy drive and a no brand video card, memory
it ended up being the revision 1.01 , thats sad because its the one with VIA KT133/686A chipset

I need to clean it up a little, put new thermal paste and i hope it works.

I noticed it has many jumpers, some with unsoldered pins for " onboard audio enable/disable" and about 3 other jumpers for AC97 primary /secondary. I hope it works soldering an isa bracket and with a soundblaster16.

Wondering if anyone at vogons got this motherboard and the same revision, i would like to get a copy of the Drivers CD

and according to cpu-upgrade website this revision does not work with Athlon XP

Reply 14 of 14, by dulu

User metadata
Rank Newbie
Rank
Newbie

I will add something to the topic, because I have been looking for 7zx / 7zxr for a long time, and i`m still looking for. Well, not every revision 5.0 does not have isa. In the attachment there is a photo of my mobo. Apart from isa, dualbios and chip creative - rev 5.0 only supports FSB 100. If you want FSB133 u need 1.0 or 5.1, but all of 5.1 rev does not have ISA

To achieve 1400MHz on this board, you need an ams3b processor, not an ams3c. And finding one is almost a miracle. Personally, I managed to get one from scrap metal, but unfortunately I killed it.

And as a curiosity, I will add that finding a SDRAM module with a blue PCB is with an even greater miracle

Attachments

  • 20211027_153228dkk1g.jpg
    Filename
    20211027_153228dkk1g.jpg
    File size
    442.83 KiB
    Views
    108 views
    File license
    Fair use/fair dealing exception
  • 20211118_123932.jpg
    Filename
    20211118_123932.jpg
    File size
    1.86 MiB
    Views
    108 views
    File license
    Fair use/fair dealing exception