There's nothing better than being able to recreate your first/favorite PC! What types of games are you playing on it? Mostly DOS or Windows games too?

kikenovic wrote:

Around the turn of the century (circa January 2000) a faulty line conditioner fried my motherboard. Anyways, money was tight but […]
Show full quote

Around the turn of the century (circa January 2000) a faulty line conditioner fried my motherboard. Anyways, money was tight but a new PC was needed, so we went with the M748LMRT motherboard by PC Chips and a 433 mhz Celeron. The PC66 32MB ram (which I still keep) was reused along with a 4 GB HDD and the AT case. As time went by, I added a capture card to the only PCI slot, upgraded the ram to 64 then to 128MB, replaced the hard disk with a 40GB one and replaced the case with an ATX one. I traded this mobo in 2003 and never new of it again.

Fast forward to 2015, I saw an online ad selling the exact same mobo and this guy also had an ATX case like the one I used with it, so I bought both.

I've been doing some tweaks here and there since I got it last year, these are the current specs:

CPU Slot-1 Pentium III 550 mhz @ 366 mhz (FSB undercloked to 66 mhz)
Ram Apacer 64 MB PC133 (56MB available)
Video Integrated Sis 620
LAN Integrated Sis 900
Sound CT1600
HDD Seagate 40GB (9GB on drive C)
Floppy NEC 3.5"
Floppy NEC 5.25"
CDROM Mitumi 16x
Windows 95b

I intend to replace the PIII with a PII 233mhz (which would be the slowest CPU I can use), I'll proly keep the 64 MB ram unless DOS gives me problems (all programs working good so far).

Ah yes, BXCel. But looks very interesting having s370 along with Slot 1 on an AT board! 😁
I do remember these boards having lots of stability problems back in the day, but perhaps this could be improved with new knowledge we have now today?

I think I have a Slot 1 AT board also featuring the BXCel, I never knew it was a SiS chipset (though I never dug around to find out what it really was).

clueless1 wrote:

There's nothing better than being able to recreate your first/favorite PC! What types of games are you playing on it? Mostly DOS or Windows games too?

Alas, I still have my first PC I ever had so no point in recreating it 😢

I know more than you think about these demons (M748MR and M748MRLT):

Lord of bugs

It took some serious tweaks for my M748MR to work at top performance and quality, but now i have bright MP3 reproduction and i've been playing a DX2 game (holy cats!) and even DX6 title Heroes of Might and Magic 3 with nice and clear music and sound effects (ex.: sound of water flowing and windmill absolutely crystal clear and immersive. I just couldn't believe in such achievement.

I managed to get solidness of this thing by installing Windows 95 OSR2, an exact driver for audio onboard
and leaving DX7 + Internet Explorer 3 alone. (IE4 update freezes my computer and causes crackles if i play
MIDI files through the software synthesizer. Go figure !

• Specs: Celeron A 366Mhz and 224Mb of RAM.
  Sound driver in use: CMI8338/C3D Audio device. Can someone confirm this is the right one ??

For now i am facing just one problem: I can't use my flash drives. (SIS 7001 USB controller got a yellow exclamation).
Have you ever used them running W95 OSR2 in this particular board? (Yeah, i installed USB supplement and downloaded unofficial flash drivers).
Windows 98SE allows me the use of flash drives, but it contains IE4 or better. No joy.

Ah, stuck! I dont even know why the hell i am fixing it, but somehow this was delivered to
me for free and i am in a frenzy putting all my hardware to work. No exception.

Restauration rox after all.

Lord of hell

Now that you said - stability problems, i am making my life miserable trying to fix and
enhance these unspeakable horribles !

My spider sense tells me i am not in the right place, but i am asking for your help.
When i enter the M748LMRT BIOS, i can see Vcore is always 1v above normal - i can confirm
this because the CPU cooler gets hot, very hot. The CPU reaches 60C degrees (IDLE) in no
time and at this point i just turn off the whole thing. Jesus, the warm goes through my body !

I have two compatible processors:
Celeron 500Mhz (Mendocino based on Pentium II core) and Pentium II 333Mhz (Slot 1)
All of them have default Vcore = 2v, so Vcore = 3v is what i get (sounds like a huge bump).
Note: I have tested them using one at a time. That idea of testing both together never passed through my head. Cut it out!

There is a jumper "JP20" on the MOBO that decreases the Vcore -0.3v (for Coppermine) or
increases +0.3v (for whatever, dude), but even then i still have 0.7v above normal. Dang!

Possible solutions:

• - A Celeron 600Mhz (Coppermine based on Pentium III core) laying around and a slotket. Although I am pretty scared to carry this test due to its lower Vcore (1.7v)
  - Replacing the Voltage regulator ??? I don´t know how to test it.
  - Hydrogen ? 😖 😁 😁

Is there any healer around here ? Pretty soon this board will take my CPU with her. I can feel it.

Sure "stability problems" i've been told have nothing to do with the hardware failing on me, but you know what ? I am at the very gates of heaven. Please, help me sort 'em out. 😎

Well, PC Chips motherboards are quite variable in quality (from average to terrible). It's not outside the realm of possibility that the board was marginal when new.

clueless1 wrote:

There's nothing better than being able to recreate your first/favorite PC! What types of games are you playing on it? Mostly DOS or Windows games too?

This forum has no like button 🙁
But I clicked likes in my mind :p

Frasco wrote:

Is there any healer around here ? Pretty soon this board will take my CPU with her. I can feel it.

Well,one thing that will quite surely prolong its life to infinite and beyond (I can't believe I'm saying this 🤣 ) might be replacing the capactiors (ECS/Pcchips are known for using G-Luxon/Teapo crap) with Panasonic/United Chemicon/Rubycon caps. I actually plan on getting one of these myself,recap the hell out of it (I have lots of caps in here) and see how far can I push it. That,or I might actually shoot for a M577,one of the best SS7 boards I've had. The ESS soundchip sounds nice as well. Should really make a nice 98SE machine out of it,assuming it has USB (for my mouse,since my mouse bracket broke).

Considering it's vintage, even good caps might be at the end of the bathtub curve. It depends on the usage pattern. I can definitely recommend cap replacement as well.

PcBytes wrote:

Well,one thing that will quite surely prolong its life to infinite and beyond (I can't believe
I'm saying this 🤣 )

Don't be shy. That's the place for me. 😀 Not to mention this is so "Star Trek" and the boundaries of the
universe.

And so, after reading the suggestions and watching one video in this matter, i measured the capacitors in
the V.R.M. area (nearest processor) and there are some of them shorted (four). What the hell !

Maybe we found out the solution. I am not saying the problem is solved, cause we never know the
extent of the damage, but seems promise. i just have to replace them (soldering is hard as hell, whereas
changing electrolytic capacitors is easy enough).

And i realized every second hand hardware that brings me down seems to have a couple of these shorted caps.
Overcharge ? Age ? Brand (quality) ? I think the problem is more about lack of care. For example,
a bad quality PSU, a slightly pulled card while the system is ON and i guess the list go on.
People don't love hardware as much as i love it. 😠

PcBytes wrote:

Well,one thing that will quite surely prolong its life to infinite and beyond might be replacing the capacitors (ECS/Pcchips are known for using G-Luxon/Teapo crap)

Brand of capacitors used in the M748LMRT is G-LUXON. Right on.
Run to the hills ? I think i am missing something here.

gdjacobs wrote:

Considering it's vintage, even good caps might be at the end of the bathtub curve. It depends on the usage pattern. I can definitely recommend cap replacement as well.

Now that i diagnosed the motherboard, i don't see the need for a total recap.
The capacitors remaining are healthy, how can we determine their final hour ? Bathtub curve ? I assume you
mean "end of life" ? Who in the hell would be using such an old and infamous motherboard? Yeah, maybe it
was agressively overclocked in its hey days or something like that. God only knows 😀

I'll bluff this time. Oh my god, that's not exactly what I am trying to say. I mean: I want to see what will
happen if i continue to use the old caps.
* please be patient with my dumbness. Sometimes I discuss even with docs and dentists. Like, i just want
to absorb some info from you people (Are those G-LUXON so atrocious ?).

Aditionally, I've been told to remove only one shorted capacitor and see what happens. In other words, see
if all other problematic capacitors are fixed (meaning much less hassle). That makes more sense to me.

Thanks, you both. Really appreciated. Ahahahah Hold on M748, I'm on the way...

PcBytes wrote:

I actually plan on getting one of these myself,recap the hell out of it (I have lots of caps in here) and see how far can I push it. That,or I might actually shoot for a M577,one of the best SS7 boards I've had. Should really make a nice 98SE machine out of it,assuming it has USB (for my mouse,
since my mouse bracket broke).

My M517 had USB connectors, so the M577 is fine, but Windows98SE is so smooth on my working M748MR.
It is important to mention:

• A M748MR supports up to P3 Katmai 500Mhz in Slot 1 (couldn't find a BIOS update for this gal)

• A M748LMRT v3.3 originally supports up to P3 800Mhz in Slot 1 and Celeron on socket 370 (didn't bother with BIOS update because as i told you, it is out of order

3D games is a no go! Don't even think about it. Don't do it, fellow. 😢 Final Reality, a simple
benchmark, lagged when using the onboard 3D accelerator. How about my experience with FIFA series!?
A ridiculous thing. Can't get that out of my head !

For this matter, i have a powerful Voodoo 3 3000 PCI and i wonder what a fast P3 would produce paired
with it. Wings to fly ?
i could make some comparison just for the hell of it. 😈

I wish you good luck if you start the journey.

Frasco wrote:

Now that i diagnosed the motherboard, i don't see the need for a total recap. The capacitors remaining are healthy, how can we d […]
Show full quote

gdjacobs wrote:

Considering it's vintage, even good caps might be at the end of the bathtub curve. It depends on the usage pattern. I can definitely recommend cap replacement as well.

Now that i diagnosed the motherboard, i don't see the need for a total recap.
The capacitors remaining are healthy, how can we determine their final hour ? Bathtub curve ? I assume you
mean "end of life" ? Who in the hell would be using such an old and infamous motherboard? Yeah, maybe it
was agressively overclocked in its hey days or something like that. God only knows 😀

I'll bluff this time. Oh my god, that's not exactly what I am trying to say. I mean: I want to see what will
happen if i continue to use the old caps.
* please be patient with my dumbness. Sometimes I discuss even with docs and dentists. Like, i just want
to absorb some info from you people (Are those G-LUXON so atrocious ?).

Aditionally, I've been told to remove only one shorted capacitor and see what happens. In other words, see
if all other problematic capacitors are fixed (meaning much less hassle). That makes more sense to me.

Thanks, you both. Really appreciated. Ahahahah Hold on M748, I'm on the way...

End of life is a logistical determination based on (among other things) reliability requirements and probability of failure. Individual component failures for caps (and many other electronics) are statistical in nature. Once the component reaches a particular age, the probability of failure increases rapidly.
https://en.wikipedia.org/wiki/Bathtub_curve

Without removing and testing them, it's impossible to know with certainty if the caps are healthy. A compromise solution would be to pull a couple highly stressed caps, like the ones from the VRMs, and ESR test them.

clueless1 wrote:

There's nothing better than being able to recreate your first/favorite PC! What types of games are you playing on it? Mostly DOS or Windows games too?

Let's say it's one I remember fondly, it got me through a lot of stuff back in the day.

I mostly play "late era" DOS games. For example the other day I was having a blast playing TNFSSE and Star Trek a Final Unity.

I couldn't get the joystick port to work on the CT1600 so I installed an ESS 1968. Not bad actually, Doom sounds pretty much the way I remember it.

For some reason the PII 233 didn't work (confirmed to work in another mobo) so I'll keep the PIII.

On the Win 95 front I intend to play old windows games (Sega PC comes to mind) and old emulators. One of my favorite frontends all time only works on Win9x.