Pentium Pro VRM missing parts (Chaintech 6IDM) \ VOGONS

Pentium Pro VRM missing parts (Chaintech 6IDM)

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First post, by Predator99

Posted on 2018-07-10, 07:35

Predator99 Offline

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Today I received some (really) scrap boards that I bought because I spotted a Pentium Pro board in the pile. Its a Chaintech 6IDM M101.

Its not in a good condition. Some traces on the back and one cap needs to be fixed. Already found the BIOS and the RTC should also not be a problem.

DSC_7268.JPG

But what I did not expect that the voltage regulators have been removed 🙁 I have found good photos of a complete board. The one on the board itsself is a "EZ1084CT":
https://www.mouser.de/ProductDetail/Semtech/E … IfpbJ1LzhOn3w==

They are rather expansive but I think I can take use a "LD1084V TO-220AB" as replacement?
https://www.voelkner.de/products/670133/STMic … tellbar-5A.html

Bigger problem is the VRM in the socket. Here two power regulators have been removed and I have no idea what to put in there?

DSC_7269.JPG

I know I can simply buy a complete new one but I dont want to spend too much money as I dont know if the board is fixable at all.

Does anybody have a similar VRM and can take a look what parts are missing?

Thank you!

Reply 1 of 7, by eisapc

Posted on 2018-07-17, 07:46

eisapc Offline

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Never seen this board layout of VRM before, but if you can't find replacement,drop me a pm.
Still have a box full of Compaq VRMs for PPro machines.

Reply 2 of 7, by Predator99

Posted on 2018-07-25, 13:33

Predator99 Offline

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Thanks for your offer!

In the mean time I made some progress 😎
- ordered a 155681-001 Compaq VRM (8€ incl. shipment at Ebay)
- soldered a LM1084IT-3.3 Texas Instruments for the missing "EZ1084CT" - 4.50€ shipped

Also fixed some damaged traces on the back and installed a Dallas Chip:

IMG_9683.JPG

I am rather surprised the board is powering up as I really was unsure if I got the correct parts 😎

IMG_9682.JPG

However, currently it still halts after the RAM test...dont think its a major issue howver...

Reply 3 of 7, by lukas12p

Posted on 2020-06-26, 17:53

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Hi
What RTC module are You running? I have ordered few DS12C887 from China, but they are used and don't hold memory

Reply 4 of 7, by red-ray

Posted on 2020-06-26, 18:09

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I have modified the ones I have to take a CR2032 as per https://www.classic-computers.org.nz/blog/200 … attery-chip.htm

Reply 5 of 7, by lukas12p

Posted on 2020-06-26, 19:11

lukas12p Offline

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red-ray wrote on 2020-06-26, 18:09:

I have modified the ones I have to take a CR2032 as per https://www.classic-computers.org.nz/blog/200 … attery-chip.htm

Thank You, that works now 😀

Reply 6 of 7, by S2 Sedan

Posted on 2024-02-03, 16:18

S2 Sedan Offline

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Hi,

can you backupo and upload the BIOS please?
I got this board, but it does not boot 😒

Reply 7 of 7, by weedeewee

Posted on 2024-02-03, 16:27

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S2 Sedan wrote on 2024-02-03, 16:18:

Hi,

can you backupo and upload the BIOS please?
I got this board, but it does not boot 😒

Next time do your due diligence in searching for what you need.
For now https://theretroweb.com/motherboards/s/chaint … ch-ct-6idm#bios is where you can find it.

Right to repair is fundamental. You own it, you're allowed to fix it.
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Do not ask Why !
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