VOGONS


First post, by NarakuITA

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Hi everyone,
I'm working on upgrading an old IBM 330 desktop (model 657759T) running Windows 98 SE. I’d like to confirm which processors are compatible and useful for this system. Here's what I’ve gathered so far:

🖥️ System Info from BIOS:
Machine Type/Model: 657759T

Flash EEPROM Revision: LVKT37AIT

System Board ID: X94VA1MXA27

System Serial Number: 559V1X2

BIOS Date: 03/19/99

The system currently runs a basic SY045 200 MHz CPU, and I’m considering an upgrade.

I asked AI bing.

Compatible CPUs for IBM 657759T (Socket 7) Intel Pentium MMX 233 MHz - 32 KB - Best compatibility, ideal for Win98 AMD K6-2 300 […]
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Compatible CPUs for IBM 657759T (Socket 7)
Intel Pentium MMX 233 MHz - 32 KB - Best compatibility, ideal for Win98
AMD K6-2 300 MHz - 64 KB - Faster, supports 3DNow!, BIOS-dependent
Cyrix 6x86MX PR233 - ~200 MHz - 64 KB - Works, but runs hot
WinChip 2 200–266 MHz - 64 KB - Very low power, fully compatible
Pentium OverDrive 180/200 MHz - 16 KB - Designed for upgrades, safe choice

According to him, my motherboard supports up to 233Mhz MMX.
Now my question is is this true or is it better to stick to 200Mhz MMX?
I found these two processors, but I don't know their actual compatibility.
https://www.ebay.co.uk/itm/275187385835?&mkri … 94&toolid=10001
or
https://www.ebay.co.uk/itm/226865825288?&mkri … 94&toolid=10001

Reply 1 of 4, by weedeewee

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SY045 seems to be a normal Pentium 200, which does not have split voltage
Pentium MMX, AFAIK, has a split voltage rail, where like 2.8v serves the core and 3v3 serves the IO.
I have never tried it, and 0.5v seems to not be very much higher, I suspect that the higher core voltage will lead to increased power dissipation.

I'm trying to find if you systemboard supports split voltage or not but at the moment haven't been having much luck finding that.
edit: According to this http://ps-2.kev009.com/pccbbs/commercial_desk … op/s78h5083.pdf , mentioning only 054C, I'm going to say that your mainboard does not support split rail cpus.

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Reply 2 of 4, by NarakuITA

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If I understand correctly, I can't put processors higher than 200MHz? Yes, I have a normal processor, but since I found an MMX, can I put a 200MHz MMX?

Reply 3 of 4, by weedeewee

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NarakuITA wrote on Yesterday, 18:59:

If I understand correctly, I can't put processors higher than 200MHz? Yes, I have a normal processor, but since I found an MMX, can I put a 200MHz MMX?

no you did not understand correctly.

Pentium MMX processor = 2 voltage rails, Vcore = 2.8v Vio = 3.3v

Pentium processor = 1 voltage rail, Vcore = Vio = 3v3

difference between 200 vs 233 is clock multiplier, 3x vs 3,5x , which tends to be fixed so in a way just doesn't even matter.
also, as for all I remember, clock multiplier for 3,5x is same setting as 1,5x

but to answer your question, can you put a 200MMX, as far as I know, No, due to the need for split voltage rails.
Will it work if you put a 200MMX on there? I do not know. The cpu core will be overvolted.

Right to repair is fundamental. You own it, you're allowed to fix it.
How To Ask Questions The Smart Way
Do not ask Why !
https://www.vogonswiki.com/index.php/Serial_port

Reply 4 of 4, by NarakuITA

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I think you're right. What a shame!