Re: Newbie to 286 systems, Ram Cards, etc.
Posted on 2018-05-13, 08:01
Your board has SIPP slots, I would use them before resorting to RAM cards.
Re: Identifying motherboard socket 3
Posted on 2018-05-12, 19:16
Dataexpert Expertboard 8046
Re: Strange issue with Chaintech 5VGM
Posted on 2018-05-12, 18:34
Nice work there, congrats! What do you use for re-soldering those chips, hot air or just a soldering iron? As for your problem, i guess a bad via. Have you checked the traces that pass under the capacitors? I have a SS7 board (forgot which one!) that has some traces corroded by a capacitor near the …
Re: Help with 286 motherboard (DTK PTM-1030)
Posted on 2018-05-06, 15:03
Well, i got myself a new soldering/desoldering station (ZD-917) a couple of weeks ago, and that reignited my interest in my broken boards. I already found a toasted MC14069 hex inverter on this board , but unfortunately after replacing it the board is still as dead as before. On the DTK board i …
Re: Help with 286 motherboard (DTK PTM-1030)
Posted on 2018-05-05, 21:45
Found the problem, it was inside the VL82C100 peripheral controller. Took my chance and transplanted the chip from another board which had it socketed - it was so tight that i couldn't extract it with the PLCC tool, i only managed to chip away one corner of the package (hence the ugly diagonal …
Re: 486 questions
Posted on 2018-05-01, 21:20
Here are the settings for your motherboard: https://web.archive.org/web/20020603034300/http://www.physics.mun.ca/~dbpynn/mboard/mboard.html Don't use regular (non-rechargeable) batteries in a place where they will get charged. J1 should be the external battery header, you can connect there a pack of …
Re: Help identify 286 Bord and troubleshoot
Posted on 2018-04-28, 23:07
Just throwing in some ideas: - ESD damage - corrupted BIOS (eproms can flip some bits over time) - cold solder joints at the Headland chipset or the CPU - try starting up your board while applying some pressure to these chips. This must be done on a hard surface to avoid bending the board.
Re: Fake cache board, reboot loop after adding real cache
Posted on 2018-04-27, 22:39
I am happy to report that the problem is gone after fitting the two chips, and that 74HCT244 works perfectly instead of 74F244 which i couldn't find anywhere. Thanks again for your advice, keropi! Filename 4SGS-3VL working.jpg File size 436.99 KiB Views 902 views Filename 4SGS-3VL speedsys.jpg File …
Re: Keyboard Error on post, 386DX-40
Posted on 2018-04-27, 05:54
KB data and KB clk should have continuity to two pins of the keyboard controller, 1 and 39 (cannot tell now which is which). Check your board for a corroded trace or via in the battery/KB connector area.
Re: Fake cache board, reboot loop after adding real cache
Posted on 2018-04-26, 08:50
@keropi - thanks, i'll try that. The pic from the net is below, the passives seem the same - mostly unpopulated 😀 @Tiido - forgot to mention, it's a Socket 3 board, so it should work with 4 chips. Filename aaa05s-l1600 (3).jpg File size 387.48 KiB Views 969 views
Fake cache board, reboot loop after adding real cache
Posted on 2018-04-25, 23:46
Tried today to add some real cache instead of the horrible soft-plastic blocks pretending to be cache chips on a (Azza?) 4SGS-3VL board. First i removed the hard-wired "jumpers" and soldered some headers instead, then i filled the first bank with four 512kbit chips and a 256kbit as TAG RAM, set the …
Re: Aopen/Acer AP43 - need VRM info
Posted on 2018-04-24, 20:50
After fitting the missing parts (minus the molex plug, for which i have no use) and a mandatory BIOS update, the board works fine with an Am5x86-133. I was even able to run Landmark, Norton Sysinfo and Speedsys at 160MHz (but Topbench crashed with a divide overflow). Thanks again for your help! AP43 …
Re: Aopen/Acer AP43 - need VRM info
Posted on 2018-04-23, 23:00
Deksor - Thank you very much, really really appreciate your effort! I happen to have one LT1085 in my parts box, bought it for installing it on another Socket 3 board (TK8948F) but i had no time to fiddle with that. And now it will go on the AP43. PCBONEZ - I'm not trying to mod anything, it's just …
Aopen/Acer AP43 - need VRM info
Posted on 2018-04-19, 22:06
Hi folks, Got this board today: http://jippel.de/boards/board22-1.jpg Well, not my photo but it's identical. It looks almost brand new, and i love its looks and the way that it seems more advanced than the usual boards from the era (SOIC instead of DIP chips, SMD and even a few that look like solid …
Re: faked cache chip or stupid bugged bios?
Posted on 2018-04-19, 21:50
Here are my results (speedsys and cachechk with cache enabled and then disabled, landmark only with cache enabled). Tightest cache timings, main memory 1WS. https://imgur.com/a/IRovBjv
Re: Help with Octek Fox M 286 (broken chip)
Posted on 2018-04-14, 09:27
Where did you get it at that price? Do they have one more? 😁 Also, one of the dip switches allows to choose between 0 and 1 wait states, and there is also a jumper for ram compatibility - forgot which one, but it's all in the manual.
Re: Motherboard can't hold CMOS settings
Posted on 2018-04-11, 23:22
Please follow PCBONEZ 's advice and try to trace the circuit from the battery positive to pin 102. You have already established that D1 is part of the circuit, and it receives the current. Next try to follow the trace that leaves the cathode, i think it will be quite easy as i see this circuit use a …
Re: Motherboard can't hold CMOS settings
Posted on 2018-04-11, 21:17
I'm sorry, for reasons i cannot even imagine it seems that yesterday i was looking at a completely different motherboard (Shuttle HOT591P). Now, being certain that i'm looking at your board, i guess that D1 is the diode in question. With everything disconnected, only the battery inserted, and …
Re: Motherboard can't hold CMOS settings
Posted on 2018-04-10, 21:52
Ok, out of curiosity i've checked this on two S7 boards from my stash that use the same chipset, Azza PT-5VMD and LuckyTech P5MVP3. On both of them i have measured around 2.85v at pin 102 (board not powered up, not connected to anything, only the battery fitted), and in both cases there is a SMD …
Re: 2nd 386 External Battery Help
Posted on 2018-04-10, 21:43
The two chips are equivalent, just different manufacturers. Up to 6 volts should be ok, no worries at 4.8. Edit: seen the pictures, it's PLCC vs QFP. Still the same chip.
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