Some parts that, from a distance, looked like they might also be damaged, but were revealed to be just a little off-kilter when viewed under a microscope.

These first few SMD capacitors are located adjacent the CPU cache. I removed one of them to measure, and found it to be 22 pF. It's a 0603 capacitor (6mm x 3mm), quite small, but not the smallest I've replaced. It was large enough that I could still hand solder with a fine tip, rather than needing to use solder paste and hot air.

I placed a layer of tacky flux, positioned the capacitor, and attached it from one side, then the other. To ensure a good connection, I apply flux on top of the capacitor afterwards, and reflow the solder again. This is to make sure that the joint isn't spoiled by any oxide on the SMD part. It's harder to do this in the beginning, because the part is so small, as it tends to stick to the flux applicator, and get carried away. Likewise, it's difficult to place if it's covered in flux, and it wants to stick to the tweezers.

I only took photos of the first two capacitors I replaced here, as the others are exactly the same. See if you can tell which ones are new from the final photo. (Hint: it's the four shiny ones.)

Also see my thumb, provided for scale.

Im following this with great interest, always like to see old hardware repaired and bought back to life and a nice integrated HX board is worth the effort.

I've seen this board crop up a few times, but never with both the integrated video and General MIDI option. It must have been very expensive at the time, if it's this hard to find one among those that still exist.

Soldering an SMD resistor looks exactly like soldering an SMD capacitor, only with different colors. And they're usually shorter. Here are some photos of before and after, as well as some more entertaining compositions to make things a little bit more interesting.

This resistor was measured at 1K Ohms. I felt a little guilty separating them, as they seemed to have grown attached.

Here are a few more, for entertainment. I also included an uncropped photo, so you can see how I take photos through my microscope by holding my camera up to the lens. This is why they're a bit washed out and not always in focus. My microscope does not have a camera attachment, so this is the only way that I can capture a picture.

I wonder how hard it would be to rig up a camera attachment using a USB camera.

I've been wanting to start up a YouTube channel and also stream my repairs for some time. I don't yet have the proper equipment for it, and would definitely need a new microscope so that other people can see what I'm doing. I'll get there some day.

Bad news with the motherboard. It can't seem to get past POST code E6 EA, which, according to Mr. BIOS, the flash memory read OK and it's bootstrapping, but it gets stuck from there. The fact that it gets this far, means that the board isn't dead. It should just be a matter of diagnosing what's wrong with it. I don't think it's related to any of my repairs.

http://mrbios.com/techsupport/award/postcodes.htm

E6: BIOS ROM is OK
EA: Read in the bootstrap code

I have tried clearing the CMOS, lowering the CPU multipliers, and using an external graphics card in a PCI slot. I have a PS/2 keyboard connected and a CR2032 battery inserted. I also tried both a 2.8V and 3.3V 200Mhz (66 * 3) CPU.

If I remove one of the memory sticks, the system beeps a very unhappy beep. So I'm guessing that the memory needs to be installed in pairs. It also seems to be alright with the two sticks, I think. It doesn't beep at all with two.

I'll keep brainstorming, and would welcome any suggestions in the meantime.

You might want to try flashing a new bios chips with the latest bios for the board and using that to see if the BIOS is actually ok, sometimes they can read as ok but have corruption later in the bios code that doesn't show till post.

****Scratch that .. Had a second closer look and I cant see a BIOS Chips on that board so I guess its like a few other silly Intel boards that has it integrated into the chipset, that does make it difficult to diagnose BIOS issues.

Possibly the little rectangular Intel branded IC near the first two ISA slots is the Sram module, might be worth looking at that if it is to make sure its ok and getting correct voltages.

Intel motherboards from this time use a really annoying surface mount flash chip that I can't remove to flash elsewhere. The board would have to be capable of blindly flashing from a floppy disk.

The little pads alongside of it are for testing I assume .. perhaps they are also used to initially flash the IC.

Or for an alternative flash chip, in the event they need to source from a different supplier.

I've made some progress. I found two severed traces on the back side of the motherboard. They are extremely small and difficult to photograph. I scraped away some of the solder mask and wet the area with alcohol to try and increase the contrast a bit for the photo. I tested these with my multimeter; both are definitely cut.

>E6: BIOS ROM is OK

with any luck it read all the flash and computed checksum, but its possible it just checks the magic number somewhere.

as for flash chip, $3 "TSOP48 to DIP48 0.5mm pitch Interposer board pcb Board Adapter Plate" to make an adapter and flash it in something else. But I would wait with it seeing you are still finding damage 😀

I cleaned up the traces with the tip of an X-Acto knife, repositioned them carefully, then mashed them into place with the tip of my multimeter probe, pressing the surface flat, and sculpting the copper.

I wasn't confident with what material was left of the top trace, so I reinforced it with a piece of solder wick. I then covered coated the area in flux and set it all in place with a bit of solder.

Here are a few photos of the procedure, with a final one that emphasizes the scale. These kinds of repairs are very challenging to even focus on with my microscope.

That was it! Another successful repair. 😀

Also, 🤣? It looks like this S3 chip suffers from the overbright bug. That is terribly anticlimactic.

S3 AGP Cards (and possibly others) Too Bright

Welcome to the TC430HX club! 😀

Kahenraz wrote on 2022-10-28, 10:15:

That was it! Another successful repair. :) […]
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That was it! Another successful repair. 😀

Also, 🤣? It looks like this S3 chip suffers from the overbright bug. That is terribly anticlimactic.

S3 AGP Cards (and possibly others) Too Bright

20221028_061137.jpg

its a shame there isnt a way to update the S3 bios to one of the models that doesn't have the gamma bug.

There are Mr.BIOS'es for this motherboard (with their pros and cons)