VOGONS


First post, by Socket3

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Hey guys. I got a couple of these odd PCCHIPS M787CLR / ECS P6VEM2 motherboards:

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These boards were a pain to have back in the day. No AGP slot, and a rather slow C3 CPU, but for a retro-PC build, they might be intresting, since the VIA CPU can be clocked on the fly with setmul, and the ISA slot lets us use any ISA sound card for great dos compatibility. I'm not sure what kind of on-board video it uses, possibly a SiS 630 witch is less then stellar. Hopefully it comes with a Trident Blade 3D on board video, but I doubt it. The Trident is quite a bit faster then the 630 and has excelent compatibility with DOS games.

One of the boards worked after a quick recap. The culprits were the 1500uf caps, witch seemed to be OK visually, but at closer inspection:

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After recapping, the 1st board posts and seems to run OK:

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That "VIA C3 - Giga Pro CPU" is hillarious. I believe these in fact come with a VIA C3 667A CPU, making the "Gigahertz" and "Giga Pro" labels complete fabrications.

The second board unfortunatly refuses to power on. It doesn't fail to post, it will not power on. At all. Shorting the power button pins does nothing. So far I've done the following:
- looking for shorts - could not find any.
- checked all 1500uf and 1000uf capacitors. I desoldered all of them, tested them with an ESR and capacitence meter, they all tested well withing spec. No leaks, no bulging.
- checked for broken traces - and in fact found and repaired a few - board will still not power on:

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I've never seen this behaviour before. Usually the boards I play with will power on but fail to post, let out magic smoke, or trip the short-circuit protection on the PSU. This board does none of these. It's like the power button is not being engaged.

Any ideas?

Reply 1 of 2, by rasz_pl

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slowly trace your way from power button header to atx supply connector, there will be VT82C686B in the way, maybe few passives and a transistor. VT82C686B is least likely broken.

Open Source AT&T Globalyst/NCR/FIC 486-GAC-2 proprietary Cache Module reproduction

Reply 2 of 2, by PcBytes

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VIA KLE133 (VT8361) is what Google says it uses, and its iGP is a Trident Blade3D. IIRC they weren't that stellar but not the worst either.
Not that SiS 630ET/ST (which is what one of my Gericom laptop actually uses, zoinks) is better, but that one does okay-ish 3D performance, at least with a Tualatin P3.
(btw slim chances that it would have been SiS - as far as my memory goes SiS' chipset is a single-chip type, while VIA's chips were almost always NB+SB)

"Enter at your own peril, past the bolted door..."
Main PC: i5 3470, GB B75M-D3H, 16GB RAM, 2x1TB
98SE : P3 650, Soyo SY-6BA+IV, 384MB RAM, 80GB