VOGONS


First post, by Rhuwyn

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Not long ago on ebay there were a ton of these boards up for sales. Some with RAM and some without RAM. Unfortunately, I missed out on the lot with RAM and ended up settling for a buying a couple that did not have RAM. Unfortunately, I was unaware that I didn't have any 30Pin RAM left over from my glory days so I'm going to have to find some.

I know a lot of people on here bought these. I wanted to start a thread on our experience with them. What CPU's we used, how it worked for us, what video cards and controller cards we used....etc.

I found the below link that has the jumper settings. Some of the jumper settings confuse me. It looks like there is a Jumper for if the CPU speed is equal to or less then 33mhz or if it is higher then 33mhz. Then there is JP4 and JP9 which talk about speed configuration but not really clear on what they do. I want to start messing with this soon as I find my 30 pin RAM but I'm a little confused on what the jumper settings would be for say a DX2 66.

http://stason.org/TULARC/pc/motherboards/J/JO … 86-G486SVL.html

Reply 1 of 2, by Kubik

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That JP25 might be related to VLB timing. For CPU bus speed under 33MHz, the VLB could run at the same speed, however, faster timing might cause problems with some cards, thus you set the jumper accordingly and VLB runs from a separate clock.
DX2/66 will use the same setting as DX/33. I take it as there are two oscillators and you can switch between them using JP4 and JP9. One might be 33MHz (or 66MHz), the other might be like 40MHz.
Have you got a good picture of the board?
Just my 2 cents...

Reply 2 of 2, by TheMobRules

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I don't have one of those boards but there are a few things that are pretty common for VLB boards.

For a DX2-66, you want to set a bus speed of 33MHz and the 2x internal multiplier of the CPU will automatically get you the desired 66MHz.

On "CPU TYPE CONFIGURATION" use the 80486DX setting, and "CPU SPEED CONFIGURATION" in 486 boards generally refers to bus speed, so select whatever option gets you 33MHz (you can try each of those "iOSC/1" and "iOSC/2" and see which one works).

JP25 is there to prevent issues with VESA Local Bus cards when you clock it higher than 33MHz. You should leave it at "<= 33MHz" unless you do 40MHz FSB or something like that.