Re: FOREX 386 Cache board doesn't post

Posted on 2019-11-29, 00:54

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Well the OP don't have that board anymore ; I have it now :) I guess that would make you the "Other Person". Which is still an "OP". I'll check that soon, but I don't really have any hopes, as it should do something even without RAM. I don't think I've ever seen this chipset and it's been too long …

---

Re: FOREX 386 Cache board doesn't post

Posted on 2019-11-28, 23:26

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thanks guys. - That was FAST! Who cares who's first. Confirmation is always valuable. Hi PCBONEZ, haven't seen you here in a while, welcome back. Thank you. I have too much on my plate now to be tinkering with retro things, despite that I got a wild hair and bought a slew of BX, TX and Super-7 based …

---

Re: FOREX 386 Cache board doesn't post

Posted on 2019-11-28, 22:22

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The OP's board. (I think - corrected.) https://www.stason.org/TULARC/pc/motherboards/J/JETPRO-INFOTECH-COMPANY-LTD-486-MB-4F.html My board https://stason.org/TULARC/pc/motherboards/M/MICRO-EXPRESS-INC-386-FOREX-386-CACHE.html [My Board] This is what I know so far. Model: FOREX 386 CACHE OEM …

---

Re: FOREX 386 Cache board doesn't post

Posted on 2019-11-28, 20:21

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Many boards come with electrolytic capacitors that simply dry out over time. Tantalum capacitors don't. That's generally true, but not 100% true. Tantalum capacitors ARE "electrolytic capacitors", just with different chemistry & tech. (So are several kinds of Polymer caps. >> Electrolytic.) There …

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-11, 07:25

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

. The vias shown in yellow have no continuity out of their area on the surface on either side. It has to be at least a 3 Layer board or none of those go anywhere. . Filename 5500_Front-Back_01.jpg File size 76.61 KiB Views 1030 views

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-11, 05:46

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

. Inside the turquoise box is a surface ground plan. There may be others. The green boxes inside that are islands with something other than ground. L20 & L21 are not connected to ground. They jump over as do the resistors just below them. Filename 5500_pwr_3.JPG File size 188.32 KiB Views 1030 …

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-11, 01:30

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

5500_pwr_1.jpg . I don't think the power section is the problem because the chips are clearly getting 3.3v power but we need to know where the 3.3v originates to track down problems deeper in the card. As far as the chips are concerned 3.3v is the power source. . I did not notice the little "+" …

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-11, 00:48

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

. The number of Layers pertains to the number of laminate layers that have conductors. Vias are just holes that have been plated to be conductors into/through the board. 2 layer PCBs and up can have Vias. On PCBs 3 layers and up the Vias don't always surface on both sides due to internal connections …

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-10, 22:06

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

The two center pins in your power connector are ground. So long as the card isn't using a floating ground (which would be rare) they should be connected to the ground plane. I would expect it to be zero ohms between the two center pins and the negative sides of the small lytic caps. .

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-10, 21:54

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

What do you mean with ground plane? If I understand correctly there should be a place on the card that is the ground plane, but I can't find it. Sorry. you did so well with the caps that I assumed you knew that stuff. I will try to find a tutorial online and if not I'll make some drawings. (I need …

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-10, 16:45

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

Before we go much further have you tried different firmwares? I dunno which are good or bad. Just know there are more than one. .

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-10, 14:44

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

This is just to let you know I didn't go *poof* on you. I'm rather swamped ITRW yesterday and today. I will be on the weekend too but I should have time on Friday. Try the TP's this way... [DC Volts Checks - with it setup so the problem is in effect.] TP (+ lead) -to- Ground (- lead) -- Compare to …

---

Re: Acer Acros Cache Question

Posted on 2018-05-07, 22:19

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Do you have the BIOS string?

---

Re: Help identify 386 Board

Posted on 2018-05-07, 21:48

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Murugan wrote: Do you have the pieces to make it boot? The BIOS string can help you get started. I've been saying that for two days. The OP showed a decoder site he uses so he appears to know how. .

---

Re: A Permanent Solution to the Dell 'Fake ATX' Power Supply Problem?

Posted on 2018-05-07, 21:43

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thank you everyone. The pins typically come in 9a, 11a, 13a but some smaller manufacturers do make other sizes. At some point the ATX PSU Standard started specifying 13a pins but much of the industry ignores it. Since there is no way to tell which pins got used the safe bet is to assume 9a pins. …

---

Re: Help identify 386 Board

Posted on 2018-05-07, 21:20

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Sorry but carpet is not an insulator. As to static it's actually a GENERATOR. When the fibers rub together carpets create brand new static which travels into other things. Any one that has ever walked across a carpet and gotten zapped by a door knob has experienced it for themselves. I once had a …

---

Re: Voodoo 5 5500 AGP freezes PC

Posted on 2018-05-07, 19:41

by

by PCBONEZ

in Marvin \ Video

in Marvin \ Video

That list will help. Nice find. I've been spending some of my breaks looking for a VSA100 pinout. No luck so far. (Bad back. I take back breaks. Helps that I am my own boss.) I don't want to get your hopes up. I could do this in my own shop with my tools but through the Internet with someone else's …

---

Re: Strange battery setting on AST 486

Posted on 2018-05-06, 19:29

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

If you can straighten the pin without breaking it then you won't need a new holder. Mini pliers might get the job done without even removing it. I can't tell where anything is connected from the photo. Can't even tell if solder is needed. It might be a press-fit. You have + and - and 3 pins. It …

---

Re: A Permanent Solution to the Dell 'Fake ATX' Power Supply Problem?

Posted on 2018-05-06, 14:16

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

@ jamesbeat Do you know the part number for the stock Dell PSU? I want to look at the rail ratings to see if all those extra pins are even necessary.

---

Re: Help identify 386 Board

Posted on 2018-05-06, 11:59

by

by PCBONEZ

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The ESD protections that are supposed to be in place and those that actually are in place are two different things. Front panel ports on consumer cases rarely have adequate protection. Some motherboards don't have adequate protection. Intel 865 boards were notorious for blown USB ports because Intel …

---