PARKE wrote on 2025-04-12, 10:25:

Matt The Cat wrote on 2025-04-11, 12:03:

I think I have seen this, but yeah. My motherboards voltage regulator is designed for 1.8 to 2.8 volts. LX1664CD

According to the spec sheet of the LX1664 it supports the range from 1.3 volt to 3.5 volt.
https://mm.digikey.com/Volume0/opasdata/d2200 … LX1664%2065.pdf

Since the spec sheet includes: Regulation Accuracy 1.8V≤VOUT ≤2.8V

Maybe that just means it garentees accuracy in that range, but can go as low as 1.3

So if I used a slotket with VID to set a tualatin the be read as 1.5 volts. It shouldn't overvolt the CPU or not boot?

Grem Five wrote on 2025-04-12, 16:04:

Matt The Cat wrote on 2025-04-12, 15:56:

PARKE wrote on 2025-04-12, 10:25:

According to the spec sheet of the LX1664 it supports the range from 1.3 volt to 3.5 volt.
https://mm.digikey.com/Volume0/opasdata/d2200 … LX1664%2065.pdf

Weird this page and whatever chatgpt sourced (which may have been this or a similar page) says 1.8 to 2.8? I wonder what's up with that...

https://www.digikey.be/en/products/detail/mic … LX1664CD/701532

I would guess the link you provided is for LX1664CD which is based on LX1664 but not identical in output.

All pages for the LX1664CD use that same spec sheet for reference. So I would guess those details apply to this unit.

Matt The Cat wrote on 2025-04-12, 18:04:

All pages for the LX1664CD use that same spec sheet for reference. So I would guess those details apply to this unit.

I realized that when I actually did a Google search for LX1664CD.

I have tried Tualatin cpus in some of my s370 boards, either they boot or do not but have not hurt a cpu yet..... yet..

Just my personal results.... mileage might vary.

Grem Five wrote on 2025-04-12, 18:52:

I realized that when I actually did a Google search for LX1664CD. […]
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Matt The Cat wrote on 2025-04-12, 18:04:

All pages for the LX1664CD use that same spec sheet for reference. So I would guess those details apply to this unit.

I realized that when I actually did a Google search for LX1664CD.

I have tried Tualatin cpus in some of my s370 boards, either they boot or do not but have not hurt a cpu yet..... yet..

Just my personal results.... mileage might vary.

Thank you. I guess I will test it out if it arrives. And if it doesn't boot, I'll just look into the 1100 celeron coppermine.

IT seems that the pdf's on the web do not represent the earlier CD version - I am sorry for the confusion that I created. Here a description of the CD version:

And there is one for sale on Ebay that also indicates only 1.8v > 3.5v:
https://www.ebay.com/itm/192082568394

PARKE wrote on 2025-04-13, 07:56:

IT seems that the pdf's on the web do not represent the earlier CD version - I am sorry for the confusion that I created. Here […]
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IT seems that the pdf's on the web do not represent the earlier CD version - I am sorry for the confusion that I created. Here a description of the CD version:

The attachment Microsemi Corporation LX1664CD.doc is no longer available

And there is one for sale on Ebay that also indicates only 1.8v > 3.5v:
https://www.ebay.com/itm/192082568394

Ah ha. I will just have to go with the 1100 coppermine celeron when I can. I also saw that eBay page, but I thought perhaps it only referenced the "Regulation Accuracy1.8V ≤ VOUT≤ 2.8V" on the earlier spec sheet I saw.

I think I will still give it a try. But I'll be careful. This document also references the same data sheet from earlier. It doesn't seem that definitive. But maybe I'm wrong.

Also, I did use chatgpt, so forgive me if I shouldn't, and it mentioned the CD meant:

C = Commercial temperature range (0°C to 70°C)
D = SOIC-16 package (plastic surface-mount package)

Well I think there is still a chance that the LX1664CD is able to go down to 1.3 volt because it supports 1.8 volt and that falls in the same category via VID4 = 0. There is a motherboard on Ebay under the title [ Vintage Merit System Mainboard Intel BX Pentium III M6TBA ] wich is a version 1.5 and according to the photos of the box it supports coppermine and it has an LX1664CD installed - see photo

The MSI adaptor arrived. Surprisingly I am still waiting on the modified Teleron CPU.