I always enjoying watching your process. I have to spend hours just trying to figure out how to open the things, haha. I only have to help friends and family though so I have time to mess about.
@@SingTodayi Have you even tried opening various mobile devices, laptops, etc from different manufacturers? Without help or looking up how to do it... and without breaking something.
You could save some time at the start by checking if there is a high side MOSFET shorted by just probing the main rail and the coils since the only path between then is the high side transistor, so you should never see a low resistance. Of course that doesn't tell everything about the MOSFET, it can fail in a bunch of different ways, especially in this case since it's a dual package, but at least there is none of that "same resistance to ground on these two points". Great video by the way. Cheers!
I enjoying how you just figured out the the way to face the issue. It was so easy if you just change the board, but taking your time to analyze the failure it's great. I enjoy this video!!!
It's a great way to build confidence if you can figure out what happened to a board, even if you can't fix it. It's a lot more satisfying to say 'This board requires work I'm unable to do, or isn't economical to do' than simply 'I don't know what's wrong with it.'
Is there a good reason no one puts a fuse on vcore after the coils on the mosfet output so it does not burn through the CPU when this kind of fault happens?
A fuse requires current to blow, it doesn't blow on voltage - so by the time the current is flowing, the CPU will have already gotten zapped. Most other protection devices I can think of for voltage (such as a Metal Oxide Varistor or a Reverse Zener Diode) probably wouldn't be fast enough. Once you get down to VRMs, the power supply speeds are _really_ fast, requiring an oscilloscope to see transitions.
I was surprised you getting get the thermal camera out just to see if there was any extra hotspots. I'm more thinking that dodgy looking capacitor at the start of the video 4:50 incase that cap had blown but not shorted.
Yea it was. I think the CPU being at basically 0 was the giveaway that it was dead, which is why I didn't really spend a lot of time checking stuff. This was more of a 'this is a thing you could try doing if you have the means...'
@@Adamant_IT Watching the video, it was not clear to me, whether the 0 Ohm short was the Mosfet or the CPU itself. Would be nice to have seen a summary like: 0 Ohms on the main power rail --> CPU mosfet shorted --> after replacement, main power rail fine, but CPU itself still below 1 Ohm --> dead CPU.
Quick question Graham. Just how similar are the newer HP boards? I have a similar case and I'm wondering how hard it would be to source a new board for it as it's become a bit tired. Mine is the AMD skew. I'm also curious if the screen header pinout is similar enough between models to possibly upgrade it to a 1080p panel. It was a budget conscious second hand buy to get me by when my MSI laptop died due to people who had no business touching it playing about with drinks nearby. I was a bit put off to be sure. That said, the MOBO you installed in the HP featured in this video looks very similar if not identical to the same layout as my one so I thought I'd ask before making purchases that would inevitably wind up in a loss on my end. Thanks for all the great content. Cheers!
Broadly speaking, if it's the same chassis (in this case a 15s-fq) the board will fit and the connectors will be the same. The big thing to watch for is the position of the CPU, if the CPU is a slightly different size / position, the cooler isn't going to fit and you'll need to find that as well. The connectors for screen, KB, etc are almost always the same as long as the chassis numbers (eg, 15s-fq) match. It's uncommon to see laptops with such a broad range of mobos available, but the 15s-fq in particular is a very very common chassis, at least in the UK.
Hi I have a case when I replaced mobo on HP elitebook. The problem was that it did not turn on with CMOS battery, I had to remove it and voila notebook came to life. How could it be?
This high side short through S to D, why did it read short to ground when the mosfets were on? Is it because when it was on it connected the input directly to cpu which would read 0.4ish and when you removed it it cut the path to cpu and on input side would read high resistance again? So on the output side it should still read the same as before right? 0.3-0.4 something like that
Correct, the path to ground was through the shorted hi-side, then through the dead CPU, which connects to ground. Normally the CPU should have a couple of ohms, but this one was > 0ohm, which was the giveaway that it was toast.
Hi there. what do you use to refit the rubber strips on the bottom of laptops? I have a Dell Inspiron 5000 series machine which i abuse daily. Because of this, it spends many many MANY hours with its processor sitting in the high 80's. This has finally destroyed the glue on the double sided tape that held the "foot"? on. Ive tried general purpose double sided tape but it didnt hold a week! I'm considering Evo-stick contact adhesive but i feel that might be overkill. Do you have any suggestions? Thanks in advance
I find the original glue holds up, sometimes I heat it a little with the hot air gun on low so it turns tacky again. If I needed to replace it, Tessa tape is really good double-sided tape that I'd trust to hold it. Some CA glue (crazy glue) or contact adhesive is fine, although of course you're probably not going to get the foot off in one piece if it needs to come apart again.
No repair business wants "pyrrhic victories", that is, no one will embark on the task of replacing an IC Processor/PCH (inaccessible and also reballing). If I were the owner I would be delighted to know that the motherboard was replaced with a functional one. Thanks for sharing. All the best.
Available from www.cmizapper.com/ It shows power-on and USB 5v status, and the green LED blinks when there's USB activity, which is a good indicator that the PCH/CPU is on and working.
" try and angle it so if it catches fire, we will get a good view"!! 👏🤣😂 Is that HP a so - so laptop? It looks nice, but what do you make of the quality of build? Thank you. I think you performed all relevant troubleshooting, replaced suspected / determined defective components, and, even after follow up tests, you have done your best!
What is this "chip munk" (is it the name?) that you're using. Is it available on Amazon? Repair boring for an expert but very interesting for us. Thanks a lot and good night ...
Available from www.cmizapper.com/ It shows power-on and USB 5v status, and the green LED blinks when there's USB activity, which is a good indicator that the PCH/CPU is on and working.
Done watching, thank you very much for the informative repair video. I have learned significantly more troubleshooting & repair lessons in this tutorial video and to your other repair videos as well compared to my ENTIRE 4 YEARS OF COLLEGE due to the rotten & outdated standards of education here in the Philippines. I have now a grasp of checking potentially faulty MOSFETs via Drain to Source/Source to Drain Resistance Values. I hope you will soon have a mini-series for Schematic & Boardview-free Voltage/Power Rail Tracing[12V/18-20V Main Voltage Rail, 5V, 3.3V, CPU/GPU Core Voltage Rail, DRAM Voltage Rail, IGPU Voltage Rail, System Agent/Northbridge Voltage Rail, PCH Voltage Rail, BIOS Voltage Rail, Battery Power Rail], Proper method of testing/checking of potentially faulty Controller IC/Chips, CPU/GPU/PCH Reballing and BIOS Bin File Editing.
Yea the CPU is soldered to the motherboard. It's possible to replace the CPU if you have a BGA rework rig, but for mobos that cost around £100 on eBay it's not remotely worth the hassle.
Yes. Since the low-side connects to ground, a short through the low-side would just go to ground and not into the CPU. As far as I know, low-side shorts are very rare, it's nearly always the high-side that dies.
Why you change the driver ? Its was liquid? I think that was your mistake... It's not a gaming laptop, so a high side short usually won't hurt the cpu... Don't have ampers enough... And then the laptop circuit see the short and stop the voltage... Greatings from Portugal 🇵🇹 🌟
If you've got a hi-side short, it could be a dead driver that jammed the gate open. I've seen this first-hand many years back when I was fixing a GTX 960, I replaced a shorted hi-side, and it lasted about 10mins before blowing it again because the driver was still faulty.
Thank you so much for Helping...... Can you Please Share the Link to Buy Keyboard Please.Mi Horizon 14 Doesn't power on, here's what another tech missed... #409
Ah I keep forgetting to do that, I'll update it. Got to do a catchy title because UA-cam unfortunately, but I'll stick models at the end of the title 👌
@@Adamant_IT Man, I can't believe you fell for this scam! You damn well know those $5 Windows keys are fake, leaked or something bad like that... sooner or later prone to be banned by M$, anyway. Better extract the original OEM keys from BIOS and reprogram it into the BIOS of the other mobo, together with the laptop serial number and other sensitive info. WTF, you're not some noob who never did this in his life!
I've used hundreds of them. Never had an issue. And again, most second hand boards are already activated because they already have a key baked into the BIOS.
USB controller's in the PCH, so if it's the CPU core that's dead, the ports won't necessarily be shorted. I agree it's a good idea to check it though, as if the USB pins _are_ short, then you definitely have a dead PCH.
huh, if you have the same board also with a dead PCH sounds like something with these models is just... killing it or its killing itself... :/ or does this happen often?
The PCH on the donor board failed because of happenstance, not a VRM failure. On-chip PCHs like these are pretty fragile. Being on the CPU is great for power efficiency, but not so good for the heat the PCH gets exposed to.
@@Adamant_IT i had a theory the vrm might have died because the pch was just drawing power to death out of it. but makes sense if its susceptible to heat, which a cpu... outputs a lot off haha. thanks for your valuable input none the less! always loving these videos!
@@Adamant_IT not sure where my comment went but lets try again :) i was thinking maybe the VRM's died because the PCH drawing too much power? or do they have overcurrent protection in those mosfets? in that case it could have been PCH that killed it in both cases. its very interresting to read this info about PCH you just mentioned, makes sense why they would die easily then! keep your pc/cpu cool people! :D
@Adamant_IT not sure why my comments arent showing up, but lets try again lol i was thinking maybe the VRM's died because the PCH drawing too much power? or do they have overcurrent protection in those mosfets? in that case it could have been PCH that killed it in both cases. its very interresting to read this info about PCH you just mentioned, makes sense why they would die easily then! keep your pc/cpu cool people! :D
I always enjoying watching your process. I have to spend hours just trying to figure out how to open the things, haha. I only have to help friends and family though so I have time to mess about.
If you can't open things, don't even try fixing them please. It's not for you.
@@SingTodayi Have you even tried opening various mobile devices, laptops, etc from different manufacturers? Without help or looking up how to do it... and without breaking something.
You could save some time at the start by checking if there is a high side MOSFET shorted by just probing the main rail and the coils since the only path between then is the high side transistor, so you should never see a low resistance.
Of course that doesn't tell everything about the MOSFET, it can fail in a bunch of different ways, especially in this case since it's a dual package, but at least there is none of that "same resistance to ground on these two points".
Great video by the way.
Cheers!
I think Graham should look into this comment. Technically, it makes a lot of sense. This is from non-experts though ...
I enjoying how you just figured out the the way to face the issue. It was so easy if you just change the board, but taking your time to analyze the failure it's great. I enjoy this video!!!
It's a great way to build confidence if you can figure out what happened to a board, even if you can't fix it. It's a lot more satisfying to say 'This board requires work I'm unable to do, or isn't economical to do' than simply 'I don't know what's wrong with it.'
Excellent video. I really appreciate the troubleshootng part of the experiance!
Is there a good reason no one puts a fuse on vcore after the coils on the mosfet output so it does not burn through the CPU when this kind of fault happens?
A fuse requires current to blow, it doesn't blow on voltage - so by the time the current is flowing, the CPU will have already gotten zapped. Most other protection devices I can think of for voltage (such as a Metal Oxide Varistor or a Reverse Zener Diode) probably wouldn't be fast enough. Once you get down to VRMs, the power supply speeds are _really_ fast, requiring an oscilloscope to see transitions.
Look at that! An HP laptop that STILL has it's bottom rubber feet! I'm amazed.
Ah another good video episode for my lunch break! 😅
Excellent video , thank you
board repair...LETS DO IT
love your videos bro
Learning from your videos and always looking forward to the next, cheers.
I was surprised you getting get the thermal camera out just to see if there was any extra hotspots. I'm more thinking that dodgy looking capacitor at the start of the video 4:50 incase that cap had blown but not shorted.
What is the resistance on CPU V_CORE after replacing the MOSFETs? I'm guessing, it's still around or below 1 Ohm, which would explain the behavior.
Yea it was. I think the CPU being at basically 0 was the giveaway that it was dead, which is why I didn't really spend a lot of time checking stuff. This was more of a 'this is a thing you could try doing if you have the means...'
@@Adamant_IT You did not say that in the video Gaham, I was going to ask about why you did not check the voltages and other things!?🙂
@@Adamant_IT Watching the video, it was not clear to me, whether the 0 Ohm short was the Mosfet or the CPU itself. Would be nice to have seen a summary like: 0 Ohms on the main power rail --> CPU mosfet shorted --> after replacement, main power rail fine, but CPU itself still below 1 Ohm --> dead CPU.
Great video dude!
Thank you.
got my first soldering kit. it’s already fun!
Quick question Graham. Just how similar are the newer HP boards? I have a similar case and I'm wondering how hard it would be to source a new board for it as it's become a bit tired. Mine is the AMD skew. I'm also curious if the screen header pinout is similar enough between models to possibly upgrade it to a 1080p panel. It was a budget conscious second hand buy to get me by when my MSI laptop died due to people who had no business touching it playing about with drinks nearby. I was a bit put off to be sure. That said, the MOBO you installed in the HP featured in this video looks very similar if not identical to the same layout as my one so I thought I'd ask before making purchases that would inevitably wind up in a loss on my end. Thanks for all the great content. Cheers!
Broadly speaking, if it's the same chassis (in this case a 15s-fq) the board will fit and the connectors will be the same. The big thing to watch for is the position of the CPU, if the CPU is a slightly different size / position, the cooler isn't going to fit and you'll need to find that as well. The connectors for screen, KB, etc are almost always the same as long as the chassis numbers (eg, 15s-fq) match.
It's uncommon to see laptops with such a broad range of mobos available, but the 15s-fq in particular is a very very common chassis, at least in the UK.
@@Adamant_IT Thanks for the info. I really appreciate it.
Hi
I have a case when I replaced mobo on HP elitebook. The problem was that it did not turn on with CMOS battery, I had to remove it and voila notebook came to life. How could it be?
This high side short through S to D, why did it read short to ground when the mosfets were on?
Is it because when it was on it connected the input directly to cpu which would read 0.4ish and when you removed it it cut the path to cpu and on input side would read high resistance again?
So on the output side it should still read the same as before right? 0.3-0.4 something like that
Correct, the path to ground was through the shorted hi-side, then through the dead CPU, which connects to ground. Normally the CPU should have a couple of ohms, but this one was > 0ohm, which was the giveaway that it was toast.
@ thanks for taking the time of your day to reply to my comment, awesome work as always man
Me: I already knew it was a mosfet and screamed at the screen.🤓
You: so probably it will be a cap. 🧐
Hi there. what do you use to refit the rubber strips on the bottom of laptops? I have a Dell Inspiron 5000 series machine which i abuse daily. Because of this, it spends many many MANY hours with its processor sitting in the high 80's. This has finally destroyed the glue on the double sided tape that held the "foot"? on. Ive tried general purpose double sided tape but it didnt hold a week!
I'm considering Evo-stick contact adhesive but i feel that might be overkill. Do you have any suggestions?
Thanks in advance
I find the original glue holds up, sometimes I heat it a little with the hot air gun on low so it turns tacky again.
If I needed to replace it, Tessa tape is really good double-sided tape that I'd trust to hold it.
Some CA glue (crazy glue) or contact adhesive is fine, although of course you're probably not going to get the foot off in one piece if it needs to come apart again.
No repair business wants "pyrrhic victories", that is, no one will embark on the task of replacing an IC Processor/PCH (inaccessible and also reballing). If I were the owner I would be delighted to know that the motherboard was replaced with a functional one. Thanks for sharing. All the best.
Unless a replacement board is not economically available. I, for one, do enjoy people like Rossmann inviting Pyrrhus to s... their d.... :)
Those are two completely different PWM chip ma brother so you fully murdered the CPU
hi 21:20 what is the chipmunk that you used?
Available from www.cmizapper.com/
It shows power-on and USB 5v status, and the green LED blinks when there's USB activity, which is a good indicator that the PCH/CPU is on and working.
It's the USB C version A4612.
I had no idea these boards are intercompatible across different generations o.O
" try and angle it so if it catches fire, we will get a good view"!! 👏🤣😂 Is that HP a so - so laptop? It looks nice, but what do you make of the quality of build? Thank you. I think you performed all relevant troubleshooting, replaced suspected / determined defective components, and, even after follow up tests, you have done your best!
you should consider creating some shorts out of your material. some parts are just pure gold
I like the probes that you are using, where can i buy them from? Thanks
www.aliexpress.com/item/1005001557245171.html?spm=a2g0o.order_list.0.0.6cca1802Tr63C4
What is this "chip munk" (is it the name?) that you're using. Is it available on Amazon? Repair boring for an expert but very interesting for us. Thanks a lot and good night ...
Available from www.cmizapper.com/
It shows power-on and USB 5v status, and the green LED blinks when there's USB activity, which is a good indicator that the PCH/CPU is on and working.
Comment for the algorithm and one of my favourite electron wrangler.
i just fixed one of those the IC SY8386BRHC QqXX are common to fail
This was neat.
Done watching, thank you very much for the informative repair video. I have learned significantly more troubleshooting & repair lessons in this tutorial video and to your other repair videos as well compared to my ENTIRE 4 YEARS OF COLLEGE due to the rotten & outdated standards of education here in the Philippines. I have now a grasp of checking potentially faulty MOSFETs via Drain to Source/Source to Drain Resistance Values. I hope you will soon have a mini-series for Schematic & Boardview-free Voltage/Power Rail Tracing[12V/18-20V Main Voltage Rail, 5V, 3.3V, CPU/GPU Core Voltage Rail, DRAM Voltage Rail, IGPU Voltage Rail, System Agent/Northbridge Voltage Rail, PCH Voltage Rail, BIOS Voltage Rail, Battery Power Rail], Proper method of testing/checking of potentially faulty Controller IC/Chips, CPU/GPU/PCH Reballing and BIOS Bin File Editing.
Is that a damage component right above the upside down R22 At 5 minutes 8 seconds in the video clip otherwise fantastic video.
one thing i always hate with HP, they hide some of the screws on the bottom, but not others. Either hide them all, or none of them, preferably none
Just replaced a dead ssd in the exact same laptop today. 😂
why do capacitors and mosfets LOVE to short out so much??
Does the new motherboard contain a CPU?
Yea the CPU is soldered to the motherboard. It's possible to replace the CPU if you have a BGA rework rig, but for mobos that cost around £100 on eBay it's not remotely worth the hassle.
So highside short is more worse than lowside?
Yes. Since the low-side connects to ground, a short through the low-side would just go to ground and not into the CPU. As far as I know, low-side shorts are very rare, it's nearly always the high-side that dies.
Why you change the driver ? Its was liquid? I think that was your mistake... It's not a gaming laptop, so a high side short usually won't hurt the cpu... Don't have ampers enough... And then the laptop circuit see the short and stop the voltage... Greatings from Portugal 🇵🇹 🌟
If you've got a hi-side short, it could be a dead driver that jammed the gate open. I've seen this first-hand many years back when I was fixing a GTX 960, I replaced a shorted hi-side, and it lasted about 10mins before blowing it again because the driver was still faulty.
hey bud intresting vid
Thank you so much for Helping...... Can you Please Share the Link to Buy Keyboard Please.Mi Horizon 14 Doesn't power on, here's what another tech missed... #409
You could hav etried the original driver chip.
It's a dy laptop 🤣🤣
Skills A.
I like this vedio
If you really want people to benefit from these videos, its important your video title is the brand and model of laptop.
Ah I keep forgetting to do that, I'll update it. Got to do a catchy title because UA-cam unfortunately, but I'll stick models at the end of the title 👌
HP makes absolute garbage, They are the worst, I had one pop it's VRM running a 35 watt i3. What a joke of a hardware scam company.
But now you have lost the Windows license and need to reinstall all software?!
Replacement boards will have an active windows licence. Failing that, a windows key is $5, not a big deal.
@@Adamant_IT Man, I can't believe you fell for this scam! You damn well know those $5 Windows keys are fake, leaked or something bad like that... sooner or later prone to be banned by M$, anyway. Better extract the original OEM keys from BIOS and reprogram it into the BIOS of the other mobo, together with the laptop serial number and other sensitive info. WTF, you're not some noob who never did this in his life!
I've used hundreds of them. Never had an issue. And again, most second hand boards are already activated because they already have a key baked into the BIOS.
Another fixed laptop excellent.
I handed my HP laptop to the recyclers, 2 and a half years old and couldn't take the blue screens any more, absolute trash
If you had an idea of a dead CPU, why haven't you checked the USB ports for SHORT the very first action? Dead CPU means shorted usb ports.
USB controller's in the PCH, so if it's the CPU core that's dead, the ports won't necessarily be shorted. I agree it's a good idea to check it though, as if the USB pins _are_ short, then you definitely have a dead PCH.
Learning even from the comments of other viewers ...
huh, if you have the same board also with a dead PCH sounds like something with these models is just... killing it or its killing itself... :/
or does this happen often?
The PCH on the donor board failed because of happenstance, not a VRM failure. On-chip PCHs like these are pretty fragile. Being on the CPU is great for power efficiency, but not so good for the heat the PCH gets exposed to.
@@Adamant_IT i had a theory the vrm might have died because the pch was just drawing power to death out of it. but makes sense if its susceptible to heat, which a cpu... outputs a lot off haha. thanks for your valuable input none the less! always loving these videos!
@@Adamant_IT not sure where my comment went but lets try again :)
i was thinking maybe the VRM's died because the PCH drawing too much power? or do they have overcurrent protection in those mosfets? in that case it could have been PCH that killed it in both cases. its very interresting to read this info about PCH you just mentioned, makes sense why they would die easily then! keep your pc/cpu cool people! :D
@Adamant_IT not sure why my comments arent showing up, but lets try again lol
i was thinking maybe the VRM's died because the PCH drawing too much power? or do they have overcurrent protection in those mosfets? in that case it could have been PCH that killed it in both cases. its very interresting to read this info about PCH you just mentioned, makes sense why they would die easily then! keep your pc/cpu cool people! :D