Talk:VESA Local Bus

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This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.

the VESA Local Bus didn't have the electrical ability to drive more than 1 or 2 cards at a time.

Is this really so? I've got a 486 sitting next to me with three occupied VESA slots.
This article needs a bit about VESA slots in Pentium motherboards, but I don't know much about that. Crusadeonilliteracy 09:54, 27 Aug 2003 (UTC)

Contents

[edit] 33mhz

i'm sure i read that there were also issues in implementing vlb for 486 chips that used a 33mhz FSB is this true and if so shouldn't it be mentioned in the article? Plugwash 17:01, 21 November 2005 (UTC)

[edit] 50Mhz

I never had a problem running VLB cards at 50Mhz. The problem was with the L2 cache SRAM chips on many motherboards. 50Mhz required cache chips faster than 10 nanoseconds, preferably 6ns, which were expensive. 7ns would work and 8ns was on the edge.

With a 486 board that was stable at 50Mhz, an AMD 5x86 clocked to 200Mhz (ADW version because it ran the coolest of the PGA type) would run right up there with a non-MMX Pentium.

I never ever had a problem running any 486 board with VLB at 40Mhz. I 'hotwired' several AMD 5x86 CPUs to force them to run at 4x40Mhz (160Mhz) with EIDE multi-IO boards and various high-end video cards in the VLB slots. Plenty fast in their day but would've been better at 4x50Mhz had I been able to find L2 cache chips fast enough.
If the cache chips were fast enough, 5x86 at 200MHz and working VLB was very easy to pull off. I avoided upgrading for a couple of years by hot-rodding a 486 system to run a 5x86 at 200MHz. If you ran the hard disks and video off the VLB slots, a system like that blew the doors off a Pentium 133. You could even run Windows 2000 off it. Jsc1973 (talk) 07:59, 17 February 2008 (UTC)

[edit] Dates

The article doesn't say anything about when it was developed, by whom, what it replaced etc. The whole article just talks about it being replaced by PCI. Why did this exist in the first place? —Preceding unsigned comment added by 71.114.134.22 (talk)

I'm not sure on the details myself but I belive it was introduced because ISA was no longer sufficiant for the new graphics cards that were coming out and EISA wasn't really that much of an improvement. A quick soloution was needed and the quickest one availible was to put cards on the 486 memory bus. Plugwash 12:53, 4 August 2007 (UTC)
That's a good question, and while I can answer it informally, it should be addressed (and sourced) in the article. Anyhow, IIRC, VL-Bus came about in 1992, and made available 32 bits for the graphics interface (or rarely, other devices), as opposed to the 16 bits available on the ISA bus. This was at a time when hardware-accelerated 3D graphics and their bandwidth demands were just beginning to appear for PCs. There was supposedly a 64-bit extension as well. — VoxLuna T / C  20:39, 13 August 2007 (UTC)

[edit] Link to Bandwidth page

Although it's mentioned in the "See Also" of this article, in fact I don't see VESA Local Bus listed anywhere in the List of device bandwidths page. And I don't know what its values would be anyway -- AFAIK, it should add up to around 133 MB/s (32 bits at 33MHz nominal), but I'm not sure. — VoxLuna T / C  20:39, 13 August 2007 (UTC)