.1v isn't a big deal if it is on the rails but I would start looking for a very high quality unit if you are not comfortable. During load those spikes and dips are larger than what can be seen in the bios.

The voltage monitor on motherboards is not terribly accurate. Pay it little mind. (today's boards are better but w/e) Besides, voltage tolerances were VERY loose compared to today's standards. Hell, ATX says voltage can be 10% off in either direction and its still' "okay". But today's (quality) power supplies regulate past the 1% mark. Voltages don't really matter much until the Pentium 4 era.

Note: DOS only, no Windows or any other GUI installed.

Well, the reason i'm concerned is mainly because of the age of the motherboard, it's getting up there in years [around 15 years].

The voltage fluxuations happend more often if I overclock the CPU from 350Mhz to 450Mhz using 2.6v same with 400Mhz using 2.4v on it's normal 350Mhz speed and 2.2v the .1 -/+ fluxuations practically stop especially on the CPU voltage meter.

I'm getting some odd behaviors too when I overclock, in Quake i'm experiencing Page Fault errors and/or hardlocks if I let it run in demo mode for about 20 or so minutes, even using different stick(s) of PC-100 RAM. Hopefully I didn't hurt the CPU itself from running 450Mhz using 2.6v -- page faults and lockups happen too at 400Mhz using 2.4v. 😢

NONE of these oddities occured until lastnight. The overclock had been stable [at least I though it had been, perhaps it was not stable to begin with]. I did put on a new HSF too which is intended for Socket 370/Socket A and it has a pretty high retention. I flexed the mainboard a wee bit several times trying to get it installed (no cracking sound, no creaking sounds etc though), the CPU socket itself is not lose or anything whatsoever, everything is solid as it should be on the motherboard (no lose capacitors, no lose mosfets, no lose anything), so I doubt that I damaged anything. However, that SEEMS to be when this whole page fault issue arised (lastnight after installing the new HSF)... though the issue is probably from overclocking.

Perhaps I pushed the CPU too far having to use 2.6v to obtain 450Mhz... AND come to think of it oddites DID occure the other night when running Screamer 2, it dropped to DOS and said something about dividing error... I idiotically ignored it, rebooted and continued to stress the CPU for another hour to so @ 450Mhz with 2.6v and I think Quake errored out once -- meh. 😒

Anyways i'm back to stock speeds until my new AMD K6-III+ arrives in a few weeks, so far to good on Quake, Screamer 2 and overall system stability using stock CPU speed and voltage. **knock on wood**.

EDIT: Ok, so Quake page faulted even at stock CPU speed. 🙁

On the K5 and the K6 the FPU often fails first on overclocking, so you don't notice until you use some software that uses the FPU.
Usually DOOM runs fine f.e. but Quake crashes. It's a rather good indicator though, to find out if the CPU starts calculating wrong after overclock.

elianda wrote:

On the K5 and the K6 the FPU often fails first on overclocking, so you don't notice until you use some software that uses the FPU.
Usually DOOM runs fine f.e. but Quake crashes. It's a rather good indicator though, to find out if the CPU starts calculating wrong after overclock.

Fail as in temporarily while overclocked and it fixes itself using stock CPU speed? Or fail as in R.I.P.?

I never overclocked that much that it didn't worked at stock speeds afterwards.

Okay so the good news is, Screamer 2 in autodemo mode is running just fine using stock CPU speed; no page fault, no divide integer... all running super smoothly as it should. Maybe I just need to reinstall Quake.

If the clip on a socket-370 heatsink is turned 180 degrees it only puts pressure on one side of the cpu and much much more pressure than it should. A mistake I have done my self.
Try to reseat the cooler and be sure that the clip is turned so it puts pressure on the center of the cpu.
The retention should not be very hard, at least not on stock socket 370 coolers.
Aftermarket socket-A coolers often have high retention but that should not be a problems as long as its not flexing the board during operation. A little flexing while mounting the heatsink should be ok.
If your K6-2 has lived a long and hard life it might have degraded to a point where it cant take high voltage and speed anymore.
Then if the motherboard dosnt have good voltage regulation instability is not surprising.
That beeing said, I have never seen a CPU degrade to a point where its unstable at stock speed exept when much higher volatge have been used.
I would keep my I eye on the voltage fluktuation with the K6-3+

Overclocking always stresses the hardware. And running old hardware at its limits...

That's the main reasons why I take it SLOW with my SS7 gear 😀

66x2 is all you need for old DOS games with cache tricks.

If you need more grunt just go with a BX440 system instead.

I use a brand-new 450W XFX PSU for my ATX stuff. Visually inspect the caps, but I haven't found any issues with my boards yet. One day I will trackle the whole recapping thing however...

Mau1wurf1977 wrote:

Overclocking always stresses the hardware. And running old hardware at its limits... […]
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Overclocking always stresses the hardware. And running old hardware at its limits...

That's the main reasons why I take it SLOW with my SS7 gear 😀

66x2 is all you need for old DOS games with cache tricks.

If you need more grunt just go with a BX440 system instead.

I use a brand-new 450W XFX PSU for my ATX stuff. Visually inspect the caps, but I haven't found any issues with my boards yet. One day I will trackle the whole recapping thing however...

Yeah I inspected them thoroughly, no bulging caps, no leaks, no anything out of the orginary, so visually it looks just fine. I do need to try and solder my NEC XR385 though... one of the caps is extremely loose... the original solder is barely there and the cap "swings" ugh have no idea how that could have even possibly happen.

I really want a Sound Canvas for General Midi though to compliment my like-new Roland MT-32 I picked up on my birthday for $70 [had original box, plastic wrappings, etc]. Then keep my NEC XR385 safe and sound in an anti-static baggy.