Random hangs are so annoying! I'd trim the machine back to bare bones and see if that helps, i.e. take the sound card out, 1 RAM stick out, network card out, and unplug the CD-ROM and zip drive.

I don´t think the HX northbridge will run with just 1 RAM stick.

nemail wrote on 2023-02-19, 19:36:

Hi […]
Show full quote

Hi

so I have put together a PC with the following parts:
GA-586HX (Rev 2.x with the switching regulator)
K6 233
2x 32 MB EDO RAM 60ns
Samsung 40GB IDE limited to 32GB via jumper
Vibra 16C ISA card
Voodoo 3 2000 PCI
3Com 3C905C-TX-M PCI NIC
Enhance 200W AT PSU
100MB ATAPI ZIP Drive
CD ROM drive 52x
Windows 98 SE with patches
latest 3dfx official driver

Unfortunately the system has been freezing randomly:

- during Windows boot logo
- within DOS games
- during CTCM initialization when booting into DOS mode

During Windows games so far it hasn't crashed.

GTA under DOS (3dfx version) starts into a black screen under DOS and freezes, under Windows the 3dfx version runs flawlessly.
CTCM sometimes freezes during init, after a reset it works again. When I had a CT4500 AWE64 in it before, it would ALWAYS freeze at CTCM initialization.

RAM speed is set to 70ns already, I think @60ns it was even worse but I'm not entirely sure.
Sometimes it runs fine for hours, sometimes (mostly under DOS) it resets right away when I start a game or it freezes after a short time or when the actual game should actually start (GTA).

No caps are bulged, neither in the PSU nor on the motherboard.

What is more likely... hardware issue or software issue? caps might be flat anyway, after all.

I'm at the end of my wits here...

THX!!

Hello,

A K6-2/233 is a bit weird cpu.
At which voltage do you run it?

You could try undervolting to 2.8V and 200 or 166MHz only, and see if it is 100% stable then.

badmojo wrote on 2023-02-19, 20:53:

Random hangs are so annoying! I'd trim the machine back to bare bones and see if that helps, i.e. take the sound card out, 1 RAM stick out, network card out, and unplug the CD-ROM and zip drive.

I've already "kind of" done that, by swapping out and leaving out many components, like the VGA card (had a Permedia2 + Voodoo 1 in it in the beginning), the Sound Card (hat a MED3700 Yamaha card in it, the CT4500 AWE64 and several others), initially I even had 160 MB of EDO RAM built into it. Only thing I didn't do yet, I think, is to remove the NIC and the CD-ROM and the ZIP drive. And the motherboard of course. I even replaced the power supply and tried a different CPU (Intel Pentium 166 MMX).

majestyk wrote on 2023-02-19, 21:06:

I don´t think the HX northbridge will run with just 1 RAM stick.

I don't think any EDO system will, as the modules are only 16 bit afaik, but the CPUs need 32 bit, hence two modules at a time...

CoffeeOne wrote on 2023-02-19, 22:45:

Hello, […]
Show full quote

Hello,

A K6-2/233 is a bit weird cpu.
At which voltage do you run it?

You could try undervolting to 2.8V and 200 or 166MHz only, and see if it is 100% stable then.

K6 233, not K6-2 233 😀
This Gigabyte board selects the CPU voltage automagically. The CPU is properly detected so I assume the voltage is set correctly, but I'll double-check.
It is running quite hot to the touch though (maybe around 50°C on the heatsink), so I guess it can't be much undervolted (if at all). That CPU also has a TDP of 28W after all.

Had another go with the system, installed a ton of games, downloaded a ton of software from my LAN webserver I set up for my retro PCs to gather stuff from, did multiple downloads at a time, churning the crap out of the HDD and no crash, freeze, whatsoever. Boot to DOS, start GTA 3dfx, DS9 Harbinger, Ascon Elisabeth I. and the thing crashes/resets/freezes.
Up until I did the last bunch of stuff, it also once freezed during Windows boot. And of course, it will still freeze occasionally at CTCM initialization.

Also, my ZIP 100 drive is being recognized as B:\ in Windows, since I updated the BIOS to the last version. I guess they've added ATAPI ZIP support to the BIOS, because it gets recognized as something like "Detected ATAPI ZIP 100 Floppy" by the BIOS even if I set the IDE channel where it is connected to to "Disabled". Annoying stuff... But that just as a side-note, the crashes were there before that.

I believe the 72 pin simms are 32-bit. The bus is 64-bit. Or am I having a senior moment?

Dimms were dual (64) inline memmory modules, simms were single (32) inline memory modules. Dimms, sdram was 64-bit and you could do a single sick. Late 486 could do single simm and was 32 bit bus.

30 pin simms are 8-bit

Could possibly be due to a resource conflict (IRQ, DMA and so on). As others have said, try removing everything from the system except for the graphics card, memory and hard drive, and see if the freezes still occur. If they do, run MemTest for a couple of hours to check your memory sticks. If that doesn't show up anything either, it's likely a hardware issue with the motherboard (bad caps, cracked solder joints etc), a damaged CPU or maybe a flaky PSU.

On the other hand, if removing the extra hardware gets rid of the freezing, try adding the cards back one at a time until you encounter the problem again. That will give you a hint as to what's causing it.

Sphere478 wrote on 2023-02-20, 01:27:

I believe the 72 pin simms are 32-bit. The bus is 64-bit. Or am I having a senior moment?

Dimms were dual (64) inline memmory modules, simms were single (32) inline memory modules. Dimms, sdram was 64-bit and you could do a single sick. Late 486 could do single simm and was 32 bit bus.

30 pin simms are 8-bit

tbh i'm not sure, but might be. anyway, afaik, one needs the sticks in pairs in that motherboard...

Joseph_Joestar wrote on 2023-02-20, 05:57:

Could possibly be due to a resource conflict (IRQ, DMA and so on). As others have said, try removing everything from the system except for the graphics card, memory and hard drive, and see if the freezes still occur. If they do, run MemTest for a couple of hours to check your memory sticks. If that doesn't show up anything either, it's likely a hardware issue with the motherboard (bad caps, cracked solder joints etc), a damaged CPU or maybe a flaky PSU.

On the other hand, if removing the extra hardware gets rid of the freezing, try adding the cards back one at a time until you encounter the problem again. That will give you a hint as to what's causing it.

OK, I get that a malfunctioning component can cause intermittent issues but how do resource conflicts fit into the symptoms? Shouldn't the issues be always there then (referring to sometimes freezing @ windows boot logo, sometimes freezing at CTCM initialization)?

nemail wrote on 2023-02-20, 07:57:

OK, I get that a malfunctioning component can cause intermittent issues but how do resource conflicts fit into the symptoms? Shouldn't the issues be always there then (referring to sometimes freezing @ windows boot logo, sometimes freezing at CTCM initialization)?

Plug and Play implementation from that era was still a bit wonky. Devices competing for resources could sometimes cause issues like that, especially if multiple cards were trying to use the same IRQ and so on.

For that reason, it's best to strip the system down to the bare minimum when troubleshooting such problems.

I had same problems with K6 300MHz in GA-586-TX2. Computer just freezed in Windows and DOS within some minutes. I use this machine mostly for testing my wavetable cards. I could barely play one midi file and it was very annoying.

Couple days ago I just changed FSB freq 66->60MHz and it's stable now. I don't know yet what is the issue. Probably not the same case but easy to test.