I assume You have a manual for it, if not I can upload one.

Plugging in the speaker the wrong way round won't cause any problems, but putting it in the wrong place might.
J1 is the power on/off connector if You are using an ATX PSU as opposed to a AT PSU.
The standby led, turbo led, reset connectors go horizontally instead of vertically.
Make sure voltages for ram, cpu are correct.

Photos?

Unless Your 486 boards are exactly the same, do not mess with the bios chips. Bios error is usually because something is configured wrong.

There was a significant issue where I plugged the speaker in backwards and the PSU made a heck of a smell, but I pulled it quick and that PSU was able to power a different board later- so I doubt that did permanent damage.

If you did only flip the speaker connection, that would only reverse the polarity of the speaker - there is no power there. Was adding the speaker the only thing you did prior to that particular power up? If so, it was probably just a coincidence and something else went.

Bad smell is bad. Are you sure it was the PSU? Did you sniff around?

I assume you don't have a multimeter available?

With the speaker plugged in correctly, do you get any beep codes?

I wasn't able to find a manual but I did find a fan site with jumper settings. Apparently this board is quite popular.

100% sure it was the PSU, I tracked the smell to it.
J1 for power on off is useful, I can try an ATX- I've been using AT thus far.
I did not get beep codes, I don't have a multimeter.

Honestly it's probably hosed, isn't it? uuggh there's nothing physically wrong with it I can spot yet it's dead anyway

What a coincidence.
My M571 was on and a USB bracket (the metal) dropped from my hand on it.
Couldn't save her. I saw the smoke. I will never forget that day 😵

I refused to believe, but that was the end.

Possible cause: You haven't installed the speaker in the correct set of pins

You are not the first, if it supports something 😖
My ASUS P5NE-SLI died when i shorted the wrong pins (front panel connectors).
This mobo gave me some signal (sparkle coming from pins) but i was angry and tried again.... 😢

Oh well, i also heard a lot of good things about M571.
Let it go, Jack, let it go 😀 😀

SRQ wrote:

E: Semi related note: I have a 486 board better than my current one that beeps to a bios error. What are the risks of dropping the bios from the working 486 into the socket on the broken one?

I wanna know about the risks involved, too...

I guess my only hope is dremeling and hacking the fucking Odin RTC on the other board.
WHY IN GODS NAME WERE THESE DESIGNED TO NOT BOOT AT ALL WITH A DEAD RTC BATTERY EVEN WHEN CONNECTED TO AC POWER.

Have you opened the PSU to check if something inside it blew up or melted?

I fully agree with you regarding the RTC garbage. Non-socketed ones are especially aggravating.

This is a uh, a Biostar 8500 or something. Soldered, yep.
What a fucking crock.

I'd just like to chime in with the painfully obvious joke of "what you're doing wrong is using a PC Chips board in the first place." 🤣

That's it. I have nothing useful to say here, sorry, other than maybe check the caps? I don't think they can fail without power being applied to them, but maybe...?

This one was quite popular and having something that well documented is rare.
Regardless, rip. RIP all my socket 5/7 boards. Rest in pieces.

CkRtech wrote:

I assume you don't have a multimeter available?

Let's pretend he does, would you care to tell what you would be doing ? Check the PSU voltages or some component on the motherboard, like Imperious said >>> Make sure voltages for ram, cpu are correct

How can one self be sure about voltages for RAM ?

Man, i really think we are losing time (so what ? This one was a great motherboard):
See if you can measure the capacitors and try out those alternative tricks like foil.
Then and only then, we would say rest in pieces or burn baby burn 😈

I tried changing voltages and stuff, I've abandoned the project and assumed it to be dead.

Frasco wrote:

CkRtech wrote:

I assume you don't have a multimeter available?

Let's pretend he does, would you care to tell what you would be doing ? Check the PSU voltages or some component on the motherboard, like Imperious said >>> Make sure voltages for ram, cpu are correct

Oh. I was thinking SRQ could test the voltages from the power supply. If the PSU looks good, you could plug it into the motherboard and turn the mobo upside down and check RAM voltages from the bottom (assuming you are out of a case and on a test bench...or have an access point from under the board while mounted in the case). Boards will have their own voltage regulators on them to support multiple CPU voltages (spanning 2 to 5 volts, I believe) - it would be good to test the output legs of those guys as well to make sure they are outputting the proper voltage.

I tried changing voltages and stuff, I've abandoned the project and assumed it to be dead.

R.I.P.

I have tested the voltage of some components on a M748LMRT with a multimeter.
This motherboard is filling me with pain and driving me crazy.

Here are the results:

Can you see some pattern ? For me it is just a mess of numbers, and PC100 looks hosed.
What you say ?

PC100[*][*][*][*][*][*][*]MOSPEC [*][*][*][*][*][*][*] NEC 02583
5.0v 1.1v[*][*][*][*][*][*]3.4v 3.4v[*][*][*][*][*][*][*] 0.1v 0.9v

Vcore on BIOS is always +1v than normal, no matter what processor i use (I am not an overclocker. 😐)
Am i doing it right (the readings) ? I'm such an idiot with a multimeter and i hate shock...

Thanks a lot for the answer. 😎

Ahh. I thought you were using an older board for socket 7 stuff. Slot 1/socket 370 with both AT and ATX connectors. Interesting. Which power supply are you using? AT or ATX?

I am not sure I follow the drawing with the voltages up there. I see 5V listed under your PC100. Is this a measurement at the DIMM slot? Your board wants 3.3V SDRAM. As you are now in SDRAM-land and past the Socket 7 era, your RAM is keyed for 3.3V. If you look at the pinout online for an SDRAM slot, you will see the various places that should carry your voltages (VCC). If you measure those places, they should be 3.3V.

The thing is that this board really doesn't have jumper settings like older boards. The only real choice you make is if you are using slot 1 or socket 370. I don't think you could have a physical hardware configuration issue unless you have the wrong slot/socket selected or plugged an AT power supply in backwards.

Just a glance at your manual though. I am currently on a tablet.

The M571 is socket 7.
Yes it does have jumper settings? You have the wrong board.

E: Oh now I get it, silly you should've just started a new thread.

SRQ wrote:

you should've just started a new thread

Sorry, i guess i was in a hurry. Besides your mission is terminated. 😲

CkRtech wrote:

Is this a measurement at the DIMM slot?

Forget all about PC100. In other words, i am not measuring memory voltages whatsoever.
PC100 is written on the voltage regulator, if i can be trusted 😀

CkRtech wrote:

The thing is that this board really doesn't have jumper settings like older boards.
The only real choice you make is if you are using slot 1 or socket 370.

True dat. I am aware of this jumper and it is in the position for socket 370 as i am using
a Celeron Mendocino (PPGA).

CkRtech wrote:

or plugged an AT power supply in backwards.

I didn't do that for my sake.

You did all that in a tablet ? Damn, i own you one.