VLB SCSI?

From: jpero_at_sympatico.ca <(jpero_at_sympatico.ca)>
Date: Fri Oct 26 19:34:03 2001

> Date: 26 Oct 2001 22:36:6 +0100
> From: "Iggy Drougge" <optimus_at_canit.se>
> Subject: Re: VLB SCSI?
> To: "Chad Fernandez" <classiccmp_at_classiccmp.org>
> Reply-to: classiccmp_at_classiccmp.org

> Chad Fernandez skrev:
>
> >I would consider VLB to be classic, or at least "legacy". I guess it
> >depends on the definition. I don't think any VLB cards have been
> >shipped for quite some time. They were mainly a 486 class bus. Did any
> >Pentium or 386 class motherboards come with VLB slots?
>
> I think I've got a Pentium VLB mobo laying about in the public spaces here...

Based on OPTI chipset and very poor quality, works w/ 1 72pin simm
but severely penalizes performance. Pair up of memory simms and
performance improves but not as fast as true pentium chipsets.
Some of them can be set up either 486 or pentium.

> While I haven't seen any 386 VLB boards, I've got an AST 386 where the CPU
> (AMD surface-mount clone) is fit on a daughter card which plugs into a VLB
> slot, though it's far away from the ISA slots.

AST uses still-born CUPID slot. Usually grouped of 3 slots. I have
seen 386dx, 486 CPUID cards but they don't exhange easily on
different AST CUPID motherboard. I know because I have done that
before. AST did make pentium CPUID cards also.

> Another odd PC mobo I've got is a 486 board with ISA, possible VLB as well,
> and a DX-50 Overdrive processor. Well, that's not so strange, but in the
> middle of the board, there is a DIN connector, like a VME or Nubus connector.
> What could that be?

Sounds like AMI board for 486 or cache card upgrade for that DIN
connector. I had this one before (386dx 25 version (baby AT w/
bit of left edge bit wider than rear half. That also has this DIN
style connector for 486 upgrade). Very nice! I think that model I
had was type 19 or 39 (386-486). Would like to find one again.

The bizarre motherboard I can think of using 386sx style CPU based on
IBM 486SLC2 50 w/ 2 VLB slots and 64K cache room for extra 64K for
128K total. It does work but performance stank due to 32 bits vlb
crimped down to 16 then back up 32 and vice vesa. A vendor made them
for IBM and IBM used them in their "early clones" machine. Took me
long time to find the jumper info. Ugh.

VLB was originally designed for 486 but also works w/ 386dx cpus
based on OPTI. I had one but dumped it because the designer of it
wasn't doing good job of it w/ certain cards espcially ATI Ultra in
16bit bios mode is dead. In 8 bit mode works but very slow.

> --
> En ligne avec Thor 2.6a.

Cheers,

Wizard
Received on Fri Oct 26 2001 - 19:34:03 BST