VOGONS


First post, by GabrielKnight123

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Hi all, I found a Socket 7 motherboard "LS-P55CE" but I didnt have a CPU so I used a CPU I had in my parts cupboard but the motherboard can only support up to 166MHz with a 2.5 ratio, I put all the jumpers to run it at 166 MHz and at boot it says the 200 MHz CPU is running at 166 MHz but because of the CPU I have "Pentium with MMX SL2S9" it needs 2.8V but the motherboard has 3.3V as a default jumper setting and when I boot I can go into the Bios but it hangs at "Updating ESCD ..." I guess this is because of the different CPU for the motherboard....am I right?

Reply 1 of 7, by jade_angel

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First off, you're overvolting the CPU, which could cause some problems. It'll probably be fine with good enough cooling, but make sure your heatsink and fan are up to scratch.

If the board is actually limited to a 2.5x multiplier, then you won't be able to clock the CPU above 166MHz, but the 200MHz CPU should run fine underclocked.

As for hanging - if you're using EDO RAM, and the BIOS has an option to tell it whether you're using EDO or not, check that. I've seen some motherboards exhibit that sort of hang when configured for EDO but using FPM, or vice versa.

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Reply 2 of 7, by Deksor

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Have you tried every jumper settings possible ? My Shuttle HOT557 according to the manual can't run cpus faster than 200, but on that board, with undocumented settings, I get a 3.5x multiplier

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Reply 3 of 7, by Tetrium

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Deksor wrote:

Have you tried every jumper settings possible ? My Shuttle HOT557 according to the manual can't run cpus faster than 200, but on that board, with undocumented settings, I get a 3.5x multiplier

Pentium MMX interprets 1.5x as 3.5x internally. In a similar way the K6-2 CXT will interpret 2x as 6x.

The LS-P55CE may have undocumented jumper settings, but I'd need to take a look at the manual as I don't know that board.

edit: Can't find a manual by the model number quickly, but it apparently uses 430FX chipset which is even older than 430VX. It's unlikely this board has many options for lower voltages.

GabrielKnight123, could you upload a pic of your board? Perhaps it's listed as another manufacturer, I may be able to find it on th99.

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Reply 4 of 7, by GabrielKnight123

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I have some happy snaps of the board here:

http://s836.photobucket.com/user/sierragames/ … vpczm3.jpg.html

http://s836.photobucket.com/user/sierragames/ … qjhjf7.jpg.html

http://s836.photobucket.com/user/sierragames/ … lfmdxg.jpg.html

The last picture is of a three legged component that was missing something I think it was just a heat sink so I removed one of a board I had that was dead and Im hoping it is good enough but I would like if someone can confirm if the black component I used with a nut and bolt needs to be conductive so it can have contact with the motherboard and the three legged component, I have put a red circle around the part im talking about and If I somehow scratch everything of the heat sink it would be conductive but I left it alone because the silver soldered motherboard "square" area does not seem to connect to anything. I have just bought a 166 MHz CPU from ebay with a 3.3V rating so I will use this instead of the 200 MHz one I have.

I found a motherboard manual from here:

http://www.motherboard.cz/driver/luckystar.htm

to find it click on "lucky star manuals" at the top and then scroll down to the bottom there are 4 files in zip format.

Reply 5 of 7, by lazibayer

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JC2 2-3
JC3 1-2
should give you x3 multiplier to get 200MHz.

Reply 6 of 7, by GabrielKnight123

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Thanks lazibayer i'll give it a go but do you think it will be ok to run the cpu at 3.3v instead of 2.8v?

Reply 7 of 7, by Skyscraper

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GabrielKnight123 wrote:

Thanks lazibayer i'll give it a go but do you think it will be ok to run the cpu at 3.3v instead of 2.8v?

The CPU can handle the voltage as long as you use decent heatsink with a fan. I would check that the motherboards 5V ---> 3.3V VRM isn't overheating because of the extra power consumtion from using an overvolted Pentium MMX, if the VRM has a heatsink I think it should be fine.

New PC: i9 12900K @5GHz all cores @1.2v. MSI PRO Z690-A. 32GB DDR4 3600 CL14. 3070Ti.
Old PC: Dual Xeon X5690@4.6GHz, EVGA SR-2, 48GB DDR3R@2000MHz, Intel X25-M. GTX 980ti.
Older PC: K6-3+ 400@600MHz, PC-Chips M577, 256MB SDRAM, AWE64, Voodoo Banshee.