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Pentium CPU issue

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Reply 20 of 39, by bofh.fromhell

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Law212 wrote on 2021-02-25, 04:40:
dionb wrote on 2021-02-25, 01:10:
Law212 wrote on 2021-02-24, 19:44:

[...]
Thanks, Ill get all that info when I open it up a gain tonight.
I didnt change any jumpers at all.

Then you are definitely running the CPU 0.5V too high. Fortunately for you the P55C is one of the most overengineered pieces of silicon out there and it can take a lot of abuse - but it will get far hotter than normal, which is bad news in a cluttered, cramped case with other major heat sources too.

How would I know and what do i do?

You need to find a manual for your motherboard and jumper it correctly for your setup.
Kinda important when it comes to old hardware, its very possible to ruin components if you get it wrong =)

Reply 22 of 39, by dionb

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Law212 wrote on 2021-02-25, 04:40:

[...]

How would I know and what do i do?

How would you know?

Well, it's quite literally printed on the CPU itself:
L_00002145.jpg
(this is a black OPGA P55C, but the purple ceramic CPGA has it on there too).

As for what to do, that depends on your motherboard. With boards of this era, it's not even 100% certain (though pretty likely) that you have split voltage support. If you do, setting the correct voltage invariably involved switching one or more jumpers. To find out which, you generally look in its manual. That is also a good place to look before even considering a CPU upgrade. If it's mentioned in the manual it's supported and you have exact instructions on how to set the board correctly for it. There are certainly options beyond what manuals state - half the fun in this game is discovering undocumented jumper settings and getting stuff not even remotely designed for systems to run - but a) try walking (in-spec) before trying to run (out-of-spec) and b) even if you have the knowledge to do that sort of stuff, you still need to know which jumper does what, and a quick glance at a manual can save hours of reverse engineering effort.

So:
1) ID board. Or if you can't, get us a really good pic of it outside the case and without cards & cables attached - so we can tryy.
2) find manual. There again, if you can't find it we might be able to help, but first we need to know which board it is.

Reply 24 of 39, by PARKE

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dionb wrote on 2021-02-25, 09:00:

So:
1) ID board. Or if you can't, get us a really good pic of it outside the case and without cards & cables attached - so we can tryy.
2) find manual. There again, if you can't find it we might be able to help, but first we need to know which board it is.

The i.d. is partially visible on the board in the 1st photo, bottom right:
https://www.elhvb.com/mobokive/archive/Kaimei … 03.0/kmt5v3.pdf

https://www.elhvb.com/mboards/kaimei/km-t5-v_3/photo.jpg

Reply 25 of 39, by Law212

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PARKE wrote on 2021-02-25, 14:45:
The i.d. is partially visible on the board in the 1st photo, bottom right: https://www.elhvb.com/mobokive/archive/Kaimei … 03.0/ […]
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dionb wrote on 2021-02-25, 09:00:

So:
1) ID board. Or if you can't, get us a really good pic of it outside the case and without cards & cables attached - so we can tryy.
2) find manual. There again, if you can't find it we might be able to help, but first we need to know which board it is.

The i.d. is partially visible on the board in the 1st photo, bottom right:
https://www.elhvb.com/mobokive/archive/Kaimei … 03.0/kmt5v3.pdf

https://www.elhvb.com/mboards/kaimei/km-t5-v_3/photo.jpg

Hero.
Though my board is slightly different than the one pictured. Mine has 4 Ram slots, but two are different , longer than the two sticks already installed. ALso , I was hoping the board had a 3 pin connector for a fan so i could use a better CPU cooler but it doesnt seem to have one unfortunately.

Ill look into the jumpers for voltage tonight.

Reply 26 of 39, by dionb

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PARKE wrote on 2021-02-25, 14:45:
[...] […]
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[...]

The i.d. is partially visible on the board in the 1st photo, bottom right:
https://www.elhvb.com/mobokive/archive/Kaimei … 03.0/kmt5v3.pdf

https://www.elhvb.com/mboards/kaimei/km-t5-v_3/photo.jpg

Well spotted/extrapolated!

So, no 2.8V setting, but 2.7V and 2.9V. Both are within spec for P55C, and lower is better (unless you are overclocking and have sufficient ventilation) so I'd recommend 2.7V:

JP11 JP12 JP14   JP15    JP16    CPU VCC
2-3 2-3 1-2 1-2,3-4 1-2,3-4 3.3V & 2.7V

If that doesn't stabilize the system, try replacing the VGA card. Rage128 would be slightly cooler, but only just. A simple little 2MB S3 card would be much better for diagnostics. If that improves stability a lot, you know that it's heat (or a damaged V3) that's to blame.

Reply 28 of 39, by Law212

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Let me also ask... I've never had a computer with the turbo button. Does it actually do anything? it says 188, and when i press it is says 88. I dont think i noticed any difference when it was pressed.

Reply 29 of 39, by Doornkaat

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Law212 wrote on 2021-02-25, 16:37:

Let me also ask... I've never had a computer with the turbo button. Does it actually do anything? it says 188, and when i press it is says 88. I dont think i noticed any difference when it was pressed.

Very few boards after Socket 4 support the turbo button.
Sometimes you can turn it into a suspend switch but most likely it's simply not connected to anything on your system.

Reply 30 of 39, by Law212

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Doornkaat wrote on 2021-02-25, 17:25:
Law212 wrote on 2021-02-25, 16:37:

Let me also ask... I've never had a computer with the turbo button. Does it actually do anything? it says 188, and when i press it is says 88. I dont think i noticed any difference when it was pressed.

Very few boards after Socket 4 support the turbo button.
Sometimes you can turn it into a suspend switch but most likely it's simply not connected to anything on your system.

thanks

Reply 31 of 39, by Oetker

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Law212 wrote on 2021-02-25, 16:37:

Let me also ask... I've never had a computer with the turbo button. Does it actually do anything? it says 188, and when i press it is says 88. I dont think i noticed any difference when it was pressed.

To add to the post above, the turbo display is set to show one of two fixed speeds (set with jumpers) and doesn't get that info from the motherboard.

Reply 32 of 39, by Law212

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I tried working on the pentium 1 last night but I failed miserably and was tired so i left it, but brought it to work to work on and I think i got it. Though I will only be able to test it at home as i dont have a ps2 mouse or keyboard here.

I changed the voltage settings as shown above, I added a better fan and cooler onto the CPU and also have a small fan on top of the voodoo 3 card now. (just sitting on top for now)
I also changed the RAM. It said it was a 64 meg chip but i think its reading as 116. The previous sticks were 32 megs i think? Ill need to look into that more when im home.

Reply 33 of 39, by Tetrium

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Law212 wrote on 2021-02-26, 20:50:

I tried working on the pentium 1 last night but I failed miserably and was tired so i left it, but brought it to work to work on and I think i got it. Though I will only be able to test it at home as i dont have a ps2 mouse or keyboard here.

I changed the voltage settings as shown above, I added a better fan and cooler onto the CPU and also have a small fan on top of the voodoo 3 card now. (just sitting on top for now)
I also changed the RAM. It said it was a 64 meg chip but i think its reading as 116. The previous sticks were 32 megs i think? Ill need to look into that more when im home.

Maybe I missed it, but it would really help if you could provide us with a model number of your board.

Your memory issues sound like a compatibility issue with (basically) the memory chips used on your RAM being too new, so only 16MB is recognized from the 64MB you put in there.
Btw, you did remove the old memory modules or did you just add the newer module? This all isn't much info to go on tbh.

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Reply 34 of 39, by dionb

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Tetrium wrote on 2021-02-27, 12:01:

[...]
Maybe I missed it, but it would really help if you could provide us with a model number of your board.

PARKE figured it out but posted link, not name. It's a Jamicon/Kaimei KM-T5-V3+

Your memory issues sound like a compatibility issue with (basically) the memory chips used on your RAM being too new, so only 16MB is recognized from the 64MB you put in there.
Btw, you did remove the old memory modules or did you just add the newer module? This all isn't much info to go on tbh.

Yep, almost certainly the issue. This is an i430VX chipset board, and VX can take max 16Mb chips, so 64Mb chips will be detected/used at 1/4 of capacity. Add a 64MB DIMM with 8 64Mb chips and it will be recognized as 16MB.

To get 64MB SDRAM on a VX, you need two 32MB DIMMs with 16 chips of 16Mb each.

Reply 35 of 39, by Law212

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I just took out that stick or ram and put in what was in there before, which is 32 megs. It should be more than enough.
I am using the computer right now. It seems to be OK so far. PLayed some Doom 2, tomb raider, Street fighter alpha and hasnt crashed or rebooted yet.

Reply 36 of 39, by Law212

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My pentium has been working well. I played a bunch of games this weekend. A couple games crashed, but there was no lockups or reboots.
I was having an issue with it where when i boot into dos, the screen would turn off , so ill have to see if i still have that issue. I didnt try booting to dos yet.
otherwise my 486 now works well, the p1 works, and my p4 work. I just need a better video card for my p2 and i think im set.

Reply 37 of 39, by Law212

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Here are some pics:
This was the board removed from the case and everything but the CPU removed.
gIsX5zd.jpg

V6vXf2n.jpg

THe replacement cooler

MwGONxi.jpg

Guts
XguUCHY.jpg

I also zip tied some cables to make it a beat cleaner inside, but it didnt help a whole lot. Im also running it with the case off, just in case

Reply 38 of 39, by Law212

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So to update this a bit. I found a rage 2 + DVD GPU the other day and replaced the voodoo 3 with it. I havent gotten any reboots since , but I need to test it more.
The P1 has a 200 Mhz MMX , 32 megs of ram and now the Rage 2 +dvd ...
I tried installing and running alien vs predator and the specs say it should work, but it install and loads up (loading took ages) and when it loads its 1 frame a minute.

Also Descent 1 runs, but has slow down a lot of the time.
FX fighter, keeps giving some wierd error and quitting to desktop, but Jazz jackrabbit 2, which used to reboot the machine, now doesnt and works just fine. Same for Doom 2. Works fine , but used to reboot the PC.

I installed the Voodoo 3 2000 into a pentium 2 350 Mhz MMx machine I have , ran AvP and Descent and they ran amazingly, though that machine has 164 megs of ram

Reply 39 of 39, by chrismeyer6

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You can use speedfan with windows 98 but I highly doubt the CPU or anything will have temp sensors built into them. That came with later CPUs but it can't hurt to try. You can also use a molex to 3 pin fan header to power your fans