VOGONS


First post, by Sedrosken

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Hi, I've recently gotten an Alaris Cougar and supposedly it overclocks to a 33MHz bus for a 100MHz 486 Blue Lightning pretty well. But when I set the jumper for a 33MHz bus, it doesn't even POST -- does anyone else here have one doing that speed? How did you do it, is there something I missed?The 4C87DLC I have coming in the mail is rated for up to 40MHz. Do I also need to switch the jumper for the VLB to the other configuration? The manual says the current setting is fine for up to 33MHz, but anything faster needs the other config. I'm assuming it's configuring VLB wait states. My cache is 20ns but I can steal the chips off of one of my other boards, those are 12ns I believe, the board's a dying PC Chips M912 anyway so I'd argue it doesn't really deserve good cache...

I know I have a whole other socket for a faster CPU if I really want it, but I find the 486BL charming and feel like it'd lose a lot of its personality if I just plunk a 5x86 in there and make it just another "fast 486". However, I find the 25MHz bus to be a pretty big limit. Not only is it holding back my memory, it's holding back my VLB as well!

Nanto: H61H2-AM3, 4GB, GTS250 1GB, SB0730, 512GB SSD, XP USP4
Rithwic: EP-61BXM-A, Celeron 300A@450, 768MB, GF2MX400/V2, YMF744, 128GB SD2IDE, 98SE (Kex)
Cragstone: Alaris Cougar, 486BL2-66, 16MB, GD5428 VLB, CT2800, 16GB SD2IDE, 95CNOIE

Reply 1 of 2, by Horun

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20nS cache should be ok to 33Mhz iirc, they work fine on my Bioteq 1433/50iV with DX-66. You have 12NS on a M912 ? odd best I ever saw were 15nS on some iirc
Can't help about the Blue Lightning.....

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 2 of 2, by pshipkov

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Cougars dont overclock well.
They kind of dont overclock at all really.
Without potential hardware mods you are limited to 25/33 mhz base frequency and 3x cpu multiplier.
Also, it looks like the bl3 cpus on them are not the most potent ones.
But at least they tend to light up at 3x33mhz, not getting even a POST is extra unfortunate outcome.
Try to increase wait states in the bios and see of that gets you in dos prompt.

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