Re: 3 (+3 more) retro battle stations
Posted on 2023-07-13, 05:19
Attached you the BIOSes i have for Abit AB-PB4 revision 1.5, IDE drivers and some other things in the archive. IDE drivers are very good btw.
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2023-07-12, 16:44
If this was a VCS where we can clearly see and track versions - it makes sense to keeping all iterations in place. But this is a mere messy thread. I guess that's what prompted Feipoa to suggest keeping the most recent (complete, best) design only.
Re: Kixs's 286 to the Max Too
Posted on 2023-07-12, 00:34
do you consider soldering a 25mhz rated CPU ? good chance you are limited by the 20mhz one.
Re: motherboard repair, ISA pin B05 voltage
Posted on 2023-07-11, 17:56
Thanks for the clarification. I will keep looking then for other issues.
Re: 3 (+3 more) retro battle stations
Posted on 2023-07-11, 05:42
Quite a few extension slots on this board. Unusual for sure. L1 WB mode: I use an interposer to force things on hardware level. Works fine if BIOS is handling it. Not in this case. Ark1000VL is rejected entirely, regardless of wait states. --- I only have 2 Abit boards based on ALi M148# Their …
Re: motherboard repair, ISA pin B05 voltage
Posted on 2023-07-11, 05:21
Thanks.
Re: motherboard repair, ISA pin B05 voltage
Posted on 2023-07-10, 22:55
Not yet, just not sure if -5V plays a role for VGA, does it ?
Re: motherboard repair, ISA pin B05 voltage
Posted on 2023-07-10, 19:32
The rest of the components are fine. PSU serves 4.6V-4.8V, not ideal, but ok.
motherboard repair, ISA pin B05 voltage
Posted on 2023-07-10, 18:55
After extensive repair of a motherboard with a lot of damage it came back to life, kind of. AMI BIOS beeps 8 times - graphics card related error code. Voltage on ISA pin B05 should be -5V, but is +1.9V. Suspicious. Unable to figure out where this discrepancy comes from. Hesitant to just connect it …
Re: 3 (+3 more) retro battle stations
Posted on 2023-07-09, 22:42
After the unexpected outcome with MSI MS-3124 version 2.1 based on Contaq 82C591, 82C592 my interest in Contaq chipset piqued and wanted to see how their stuff does in the realm of 486. Addtech Galaxy II 486 revision 1.0 based on Contaq 82C596 A3, 82C599 . https://www.petershipkov.com/temp/retro_pc_ …
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2023-07-08, 07:02
To be clear, the PGA168 TI486SXL-40 mentioned (which compared to your picture does not have the "FC2-" marking), can enable, and I do enable clock double at 33Mhz FSB at 3.6v (not 66mhz FSB), the SXL was rated 40mhz FSB, so enabling clock double in the SXL for me was the only surprise. The specs …
Re: 486 motherboard FSB issue
Posted on 2023-07-03, 18:35
Check my note about how the manual is misleading, or at list this very motherboard here does not behave that way. Both pints 1 and 3 of jumpers 28 and 29 are GND, so no matter in which position you set them (1-2 or 2-3) the result is the same. The jumper cap itself must be removed to change state. …
Re: 486 motherboard FSB issue
Posted on 2023-07-03, 01:43
Spent some time on this problem today. Everything is ok with the clock generator, but there are problems with the configuration jumpers, unless i am missing something obvious. Combined picture of motherboard, clockgen frequency table + pins, some relationship lines and jumpers of interest. 1.jpg …
Re: 486 motherboard FSB issue
Posted on 2023-07-02, 07:05
Ok, the clockgen is fried. Only frequency it outputs is 8MHz.
Re: 486 motherboard FSB issue
Posted on 2023-07-02, 01:17
yeah, there is a good chance something is off with the clockgen. will verify that tonight.
486 motherboard FSB issue
Posted on 2023-07-01, 23:59
This motherboard gives me trouble. https://theretroweb.com/motherboards/s/addtech-galaxy-ii-486-ver.-1.0 For some reason the CPU runs off 8MHz FSB. So, even i set the FSB to 33 or 40 MHz the CPU does 3x8=24MHz. Tried bunch of jumper configurations - no difference. Anyone hit such issue before and …
Re: Where to obtain 110 MHz RAMDAC for ARK1000VL graphics card?
Posted on 2023-07-01, 23:57
It was a presumption that it may get you to 1024x768 resolutions. I have 2 Ark1000VLs - one like your 2theMAX and another one here. They don't go past 800x600x64K in Windows 3.1. This suits me, so i didn't investigate higher resolutions at 256 colors.
Re: 3 (+3 more) retro battle stations
Posted on 2023-07-01, 21:08
@WJG6260 With Mr.BIOS i can get the SXL2 to boot into DOS. ISA bus frequency cannot be higher than 12.5MHz. Everything works really, except level 2 cache. Do you see the same ?
Re: Where to obtain 110 MHz RAMDAC for ARK1000VL graphics card?
Posted on 2023-07-01, 19:11
Arkk1000VL can do 64k colors at up to 800x600 screen resolution. If you are ok with 1024x768x256, then this RAMDAC may help you: https://www.questcomp.com/part/4/att20c490-11m44/110195125
Re: serial mouse not detected on a 386 motherboard
Posted on 2023-07-01, 06:50
This was one of the more confusing factors. It shows on the oscilloscope screen. When push/press the board during measurement that cold joint makes contact quite consistently. We all hit cold joints at some point. Some can be forced to make contact by bending/twisting the board. Others need …
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