Question Can I repair a dead motherboard?

[eloh!]

Hello all!

I am new to this forum, and I wanted to reach out for a quick question,

I have intentionally purchased a dead ASUS Strix B250i motherboard with hopes to fix it to save some money and learn a little more about electronics and such. After performing all the troubleshooting methods I could imagine, I believe the issue involves the motherboard’s ability to deliver power to the CPU. The motherboard’s power indicator turns on, fans spin up, and integrated light strip works, but the issue is the CPU light is constantly on, hindering the system’s ability to POST. The motherboard will turn on for around 6-10 seconds, power off for a moment, and will repeat this process until I remove power from the board. I know all the components I have installed work properly, and my troubleshooting methods are listed below:

• Removed memory, one stick in each DIMM slot, tried a separate kit, nothing.
• Reseated CPU and tried different coolers in case it was a mounting pressure issue, still nothing.
• Removed and reset CMOS, still no POST.
• Used a separate power supply, the issue persists. I know these units work because I tested both on a separate board while troubleshooting my current one.
• I am using integrated graphics, so I don’t have any discrete GPU to reseat, remove, etc.
• I have not tested a separate CPU because I don’t have any compatible ones laying around, but I am using an i3-7100 and last time I checked, the CPU worked just fine.
• The socket looks good, with no bent pins or inflicted damage.

Would anyone have any other methods of troubleshooting or ideas for narrowing in on the actual issue? My current thoughts involve an issue with the MOSFETs and 8-pin EPS connector, but I can’t think of any ways to properly test and diagnose this. I am fine with soldering if needed, and I do have a multimeter laying around that could come in handy, but I only know the extreme basics in using it.

Any suggestions are greatly appreciated!

 

[eloh!]

That's the impression I get anyway. Some transistor embedded in some chip is off when it should be on ............... or vice versa. Hence that behavior with the LED's when it's trying to boot ......................... but I could just be getting the wrong impression too.

I am sorry for not seeing this message sooner. Would you know of any ways to troubleshoot this possible error? Or to verify the connections between the PSU and CPU?

 

[vov4ik_il]

Oh, okay. Since I have been fiddling with it while plugged in throughout my first experience with it and now, is it possible that there may be damage caused that may cause a lack of reading the IC?

I really can't tell...

 

[eloh!]

I really can't tell...

Okay. Hopefully I can get this figured out soon.

 

[eloh!]

Okay. Hopefully I can get this figured out soon.

Hey! I got it working again!

I just took a break from working with the flasher for the day, and upon trying it again today, it worked first try! I do still have it plugged into my motherboard, but I was just verifying that the flasher would read on a chip that I know has worked in the past. At least I know it works now.

 

[eloh!]

I just took a break from working with the flasher for the day, and upon trying it again today, it worked first try! I do still have it plugged into my motherboard, but I was just verifying that the flasher would read on a chip that I know has worked in the past. At least I know it works now.
[/QUOTE]

I am now attempting to read one of my new BIOS ICs with the flasher clip, but still no luck. If I am better off with the soldering method, how should I approach this?

I am sorry for the amount of time this project has taken, but I hope we can get this resolved soon!

 

[vov4ik_il]

I am now attempting to read one of my new BIOS ICs with the flasher clip, but still no luck.

Post a photo of your setup

 

[eloh!]

Post a photo of your setup

As of now, this is my current setup:

https://imgur.com/oAEPlW1

View: https://imgur.com/oAEPlW1

 

[vov4ik_il]

Which IC exactly did you buy?

 

[eloh!]

Which IC exactly did you buy?

I believe I had purchased the one that you linked.
Reading the IC, it says:
winbond 25Q128FVSG
1739 LH

 

[vov4ik_il]

I believe I had purchased the one that you linked.
Reading the IC, it says:
winbond 25Q128FVSG
1739 LH

Well, it should be readable, is the key in the right spot? (Dot towards the red wire)

 

[eloh!]

Well, it should be readable, is the key in the right spot? (Dot towards the red wire)

Yes, I have the dot corresponding to the red wire. Do you think there would be any of that coating on the pins preventing a proper reading like what was previously mentioned?

 

[vov4ik_il]

Yes, I have the dot corresponding to the red wire. Do you think there would be any of that coating on the pins preventing a proper reading like what was previously mentioned?

You mentioned ringing the wires to the chip pins so that shouldn't be an issue

 

[eloh!]

You mentioned ringing the wires to the chip pins so that shouldn't be an issue

Oh, I think I may have explained something incorrectly earlier. The last thing I did with my jumper wires was reconnecting them to the motherboard's BIOS header, but I had not done any ringing to the legs of the new IC, if that is what you mean. Now that you mention it, I could certainly give that a shot, if that could be a working option.

 

[vov4ik_il]

Good, keep us posted

 

[eloh!]

Good, keep us posted

I did give it a shot, but I had a really hard time getting the wire to coil around the IC’s legs. Would you have any suggestions on how I can approach this? I can look around at some ideas, but do you think I should attempt the method that involves soldering the IC to the flashing board first?

 

[eloh!]

Hello,

I recently found your tutorial post on how to flash a BIOS chip, and even after I followed all of the instructions you had mentioned, I still couldn't get a read on the IC. This time, I used a USB 2.0 motherboard strictly rather than what I had previously been doing, but still no luck. Do you think the flasher could be at fault here? Or could there be any software / driver issues with the flasher?

Thanks.

Edit: I just thought of something quite random, but I wanted to see if you have any ideas before I possibly go with this. Because I have only had luck reading the BIOS chip on the motherboard using the jumper wires, what if I desolder the old IC, place the new IC on the board, and attempt to read/write the new BIOS when on the board?
The only thing I am unsure about is how the flasher didn't successfully write to the IC previously, but that issue brought us to the conclusion that the old IC was dead in the first place.
What do you think?

 

[vov4ik_il]

Do you think the flasher could be at fault here? Or could there be any software / driver issues with the flasher?

Should not be an issue there.

Edit: I just thought of something quite random, but I wanted to see if you have any ideas before I possibly go with this. Because I have only had luck reading the BIOS chip on the motherboard using the jumper wires, what if I desolder the old IC, place the new IC on the board, and attempt to read/write the new BIOS when on the board?
The only thing I am unsure about is how the flasher didn't successfully write to the IC previously, but that issue brought us to the conclusion that the old IC was dead in the first place.
What do you think?

I think the new one you got is DOA. Hard to tell remotely.

 

[eloh!]

I think the new one you got is DOA. Hard to tell remotely.

I purchased that pack of 10 or so, and I've played with around three of them so far to make sure that I wasn't playing with a bad IC. As of right now, I haven't had any luck with any of them so far, but I could continue moving through each IC until I possibly get one working. Do you think an entire pack could be killed by something? I assumed that the IC holder is antistatic, but I really don't know.

 

[vov4ik_il]

Do you think an entire pack could be killed by something? I assumed that the IC holder is antistatic, but I really don't know.

Well, thats odd. No I think something is not makong contact then. No need to go through the whole pack.

 

[vov4ik_il]

25Q128FVSG

Oh, wait, it is a 3v chip and we use 1.8v adapter. No wonder it does not work with the adapter. In my example the chip was 1.8v too.
Take the adapter off. Do the 3v mod (which I have linked in the tutorial) and try programming again. I do not know how many times I’ve looked at it but apparently I missed it.

That would very well explain the write/verify issue you had too.
I started having long days at work, so it takes longer for me to reply, sorry.

 

[eloh!]

Hey guys!

Sorry for disappearing for so long. I recently started college and wanted to focus on that as much as I could. I didn't forget about this progress though! I want to really thank you guys for all of the help you have given me thus far, and I have another update!
Today, I did the CH341A 3.3v mod, and it worked perfectly! I got 3.3v on all of the pins tested in the instructions, and when I opened the programmer, it worked flawlessly. It read, wrote, everything was perfect and worked upon the first try. I verified the BIOS was written properly, and it was all good.

Once the BIOS was flashed and all, I put the computer back together. When I turned it on, the CPU light was still on, just like the old issue in the beginning. I know everything is connected correctly and it's a bit of a bummer that it didn't quite work out, but it's okay! I learned a ton throughout the process of this and I want to thank you guys for helping me out with it!!
If you do have any suggestions on what it could be, I would be assuming phases, etc. at this point, please let me know! This was a really fun project as a whole and I'm really happy with what I've learned along the way.

 

[vov4ik_il]

To keep digging into power delivery circuitry, you want schematics and will need a scope. I would stop here as the tooling gets significantly more expensive

 

[eloh!]

To keep digging into power delivery circuitry, you want schematics and will need a scope. I would stop here as the tooling gets significantly more expensive

That makes sense. Thank you so much for your help though, I have certainly learned a ton and I couldn't be happier with the results.