Re: Intel AA-654850-206 Advanced/ML Marl motherboard lost VRM

Posted on Yesterday, 17:49

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

You could ask this seller to remove the clamp and make a picture of the transistor / voltage regulator. https://www.ebay.com.sg/itm/Intel-Advanced-ML … 61/163829051189

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Re: How can I safely transplant a 160-pin QFP chip?

Posted on 2022-05-18, 15:34

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

so you took a fully working board and cut it to pieces to fix another one? seems dumb Not necessarily, if you´re 100% sure which one you want to keep and if you have been searching for a new (NOS) replacement chip for 5 months with zero success. Unfortunately this chipset is quite rare and there …

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Re: How can I safely transplant a 160-pin QFP chip?

Posted on 2022-05-18, 14:15

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

O.k. - yesterday I got hold of the donor-board. The BIOS chip was missing, so I gave it a try with the Symphony BIOS of my FIC 486SC-P. It started, but cache and RAM were not recognized correctly. I was unable to find an original BIOS online and now I knew the donor-chip was working so I decided to …

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Re: UM8881F motherboard hangs at C7 code "keyboard error""CMOS checksum error"

Posted on 2022-05-18, 05:35

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

It´s a Shuttle HOT433 btw. There still seems to be corrosion at / around the KB-connector. I would check the traces and vias in this area carefully for conductivity. I hope you provided a socket for the Dallas RTC before replacing it several times...

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Re: motherboard refuses to enter BIOS

Posted on 2022-05-16, 17:56

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Some AMI BIOSes demand you enter BIOS by hitting F1 when RAM size has been changed.

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Re: Compatible PC speaker for DTK Turbo XT motherboard

Posted on 2022-05-13, 08:35

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I guess you measure 5V~ when there´s no speaker connected. If there´s a 5V~ AC voltage (U) at the output and the maximum power (P) is 0,5W, the rule is: P=U²/R and hence R=U²/P => R=25/0,5 = 50 Ohm. If you connect an 8 Ohm speaker you will overload the speaker output. Look for some speaker that has …

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Re: SY-5EMA+ writing cache becomes disabled

Posted on 2022-05-11, 17:29

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

L1 cache may be independant of chipset limitations but its not independant of BIOS decisions. BIOS can disable it anytime for whatever reason be it intentional or due to a bug.

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Re: SY-5EMA+ writing cache becomes disabled

Posted on 2022-05-11, 10:48

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Even if L1 could still work fine, BIOS can do whatever it likes here. Maybe it´s a BIOS bug? You could try earlier/later versions if any exist or try a BIOS from a different board with the same chipset and super-io. Look out for MVP3 based mainboards with SMC super-io like the DFI K6XV3+ (without " …

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Re: 128 MB of RAM on 4386-VC-V motherboard

Posted on 2022-05-10, 16:28

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

You might check / clean / adjust all the contacts in the RAM-slots.

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Re: SY-5EMA+ writing cache becomes disabled

Posted on 2022-05-10, 08:57

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by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Just a guess: As far as i remember the VIA MVP(3) chipsets needed 2MB of L2 cache to cache 512MB RAM. This is probably also the case when L2 cache acts as L3 cache under a K6+ CPU. In case there´s only 512K or 1MB L2 cache on your board (you didnt tell us so far) - depending on the Soyo BIOS, L2 …

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Re: SY-5EMA+ writing cache becomes disabled

Posted on 2022-05-10, 05:58

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

What size is the onboard L2 cache? Are the two SDRAM sticks you tried the same size and what size? Is there an option in the BIOS to enable/disable memory interleave?

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Re: 775 and ISA

Posted on 2022-05-08, 08:13

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Just wondering if one of my my Socket 479 mainboards with a Winbond W83628AG PCI-ISA bridge would be capable of DMA support? https://pdf1.alldatasheet.com/datasheet-pdf/v … N/W83628AG.html

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Re: How can I safely transplant a 160-pin QFP chip?

Posted on 2022-05-02, 06:39

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Thanks to everybody for your help! I will dig out the donor-board as soon as I have some spare time and check it´s condition. It would be useful to do some basic tests to make sure the chip is in good working condition - this means to get the donor-board running first. I will report here as soon as …

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Re: Asus PCI/I-P54TP4 annoying cache detection error

Posted on 2022-05-01, 08:58

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

There´s a nice Dilbert comic about that: https://dilbert.com/strip/2009-06-29

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How can I safely transplant a 160-pin QFP chip?

Posted on 2022-05-01, 08:22

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

From my heep of unrepaired mainboards I recently pulled a FIC 486 SC-P that´s based on the "Symphony Haydn" chipset. I ran some tests and to my surprise everything seemed to be fine. But after a while the thing started acting absolutely crazy. It either wouldn´t POST at all or give some random AMI …

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Re: Asus PCI/I-P54TP4 annoying cache detection error

Posted on 2022-05-01, 07:38

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I added the header for the VRM module myself. You also have to cut some traces and add a jumperblock to enable split voltage operation. (I also added the beeper, a socket for the Dallas RTC, the PS2 mouse-connector and replaced the 1000µF capacitors.) All VIA chipsets of that area (Apollo family) …

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Re: Asus PCI/I-P54TP4 annoying cache detection error

Posted on 2022-04-30, 07:49

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Today I equipped this board with 128MB RAM and did some testing. Apparently the 256 KB L2 cache is able to cache 64MB of 128MB RAM. PCI_I_P54TP4_cache_area.JPG I also tested with 512KB L2 cache: PCI_I_P54TP4_cache512.JPG As we know Intel´s FX chipset is limited to a maximum cacheable area of 64MB …

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Re: Asus PCI/I-P54TP4 annoying cache detection error

Posted on 2022-04-29, 06:15

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

@flupke11: Thanks! My usual way to remove/replace QFP chips is to first cut all pins with a Dremel using a small metal circular saw blade. I cut the pins right where they come out of the chip. After lifting the chip out the remaining parts of the pins on the soldering pads can then be removed / …

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Re: Asus PCI/I-P54TP4 annoying cache detection error

Posted on 2022-04-28, 18:55

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Better late than never - I finally finished this project today. After replacing the second bus transceiver, L2 cache gets detected correctly now, the system boots with cache enabled and L2 cache is working flawlessly. This saved me from replacing the Northbridge and/ or the two Intel buffer chips. …

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Re: Biostar M5ATA inductor blown - repair hints?

Posted on 2022-03-11, 17:44

by

by majestyk

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

4R7 might as well be an inductor with 4.7µH. If it´s position is "L2", it probably is.

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