Worth adding that if you want to see not only if the power stage is working but also the quality of the signal it produces, you may check by using oscilloscope - probing on the coil that sits right behind the chip.
Bai Sorine, asta chiar a fost TARE !!! BRAVO !!! :D)))) era de asteptat dar nu n-am gandit... E cumva spiritual romanesc... E din categoria reparatiilor gen dresurile in loc de curea la alternator si oua in antigel cand ai radiatorul spart... Chiar ma-ntrebam odata de ce erau asa de multi romani renumiti peste hotare... si raspunsul: pentru gandirea neparametrizata, "outside the box" BRAVO!!! 👏
I was reading the datasheets when that video ended and didn't find the difference, but I think the reason why the GPU was still good is because of the catastrophic fault detection something-something that the datasheet claims it has.
Indeed, I work on GPUs a lot, and failed high-side MOSFET is about 1 in 5 chance GPU survived. When DRMOS is used, depending on the brand and quality of it the chance can rise to 3 in 5. So Sorin has outdated view on the subject really, he was so surprised the GPU was fine, when normally you do not make any assumption until checking. I must add that short on VMEM / VCTRL rails are much worse then VCORE. Memory rails seems to be more delicate and even short detection is typically not fast enough to save the memory controller.
One of the FETs in each package is used as a synchronous rectifier. If it fails short-circuit the load is protected from overvoltage. Presumably the FAULT output from the part is used to shut down the entire converter so other parts in the power path have a chance of survival. (one failed rectifier FET would short the entire multi-phase array through the winding of the inductor connected to the failed part)
Yeah the myth is that Lenovo Legion 5/7 etc 2022+ models use PTM7950 pads. I went to lenovo forum and asked, the answer from Lenovo helpdesk was "normal thermal paste" but as to what type and brand no comment on that. Personally i used recently NTH2, feels like it got hotter and doesnt boost as much as it was with the stock thermal paste (i did some benchmarks). But just for the sake of the comment, in stress tests 12700h draws 130w for a second till it hits 100*C and throttles down to 109-112W and shits around 85-94*C, RTX 3070 draws 150w in full load and if numbers dont lie, ive seen 154watt with temps ranging 64-77*C. Pretty good cooling, if you dont think about your laptop sounding like a drone and it might explode on your face or fly away at any momment....
It´s not thermal paste. It´s phase change material. It´s comes in sheets. Check mouser for "laird tpcm 7400" or "laird tpcm 5400". The one from lenovo is honeywell ptm 7950. The new phase change material does not change to a liquid, but softens at about 55 to 60 C. Phase change material is a thermoplastic with thermal conductive fillers. Thermal paste is usually silicone oil or other oil with thermal conductive fillers. If you replace the phase change on that laptop(I have the same one), the gpu will start overheating after a few months(the issue is more the hotspot), because there´s not good contact between the gpu and the heatsink, and the paste will pump out. That does not happen with the phase change material. And that´s why you see a bigger concentration of "paste" on one of the corners where the heatsink contacts the gpu. For you to see the difference, it´s better to buy a phase change sheet and try it.
Bro, Sorin heated it up to 400+ degrees and there was no melting/liquifying of that. Either the owner changed it to a regular thermal paste (which then dried up), or the laptop came from the factory with thermal paste instead of phase changing material. Either way Sorin proved the point and I am sure he saw and he is aware of the existance of PMT from honeywell, but it is not the case here.
@@ElBandito_Gaming typical thermal paste will pump out within 2 or 3 weeks mark my words the customer will complain of heat related issues after using his laptop
@@ElBandito_Gaming New phase change materials do not melt. They soften. They are thermoplastic based. The old phase change materials melted because they were paraffin based. And if the paste reached anything close to 400ºC and he touched it, i can assure you that he would burn his finger instantly. Not to mention that the heatpipes would probably burst. Just because the air is coming at 400ºC from the nozzle, it does not mean that it heats everything to 400ºC instantly... But hey, you are free to believe whatever you want to believe.
Interesting that the heatsink had pipes over the mosfets also, and the one that failed was at the end of that pipe, does that pipe have full contact with all the mosfets properly?
Please Reply: Hi, I have the same laptop. My dedicated gpu is not working in devices manager it is show the yellow sign error"Device not connected properly." I checked the board, and there are no shot circuits, but my Gpu has no heat up or anything. Should I reflow my Gpu soldier, and how risky is it?
Lenovo Legion 5 15IM05H here. On thanksgiving 🦃 the Legion 5 shutdown unexpectedly. | order a new external battery and internal battery. Still not turning back on from the video this may be a mother board, CPU, GPU, issue? Not sure how it would have gotten damaged besides normal wear and tear? First time a motherboard went out on me. Any help from anyone on where I can go next for help would be greatly appreciated
Can’t you check with the oscilloscope if the phase is working? I have seen Northwestrepair doing it several times on gpus, I believe he’s probing before the inductor
The only correct way to check the operation of Drmos is with an oscilloscope. Then you will see if it works and if it works correctly. Are there any spikes or runts during operation.
People who really know how to use an oscilloscope and understand the circuitry they are working on tend to use a scope all the time. When I did repair work it was usually the first instrument I'd use. Before the inductor is the right place. There would be a reasonably clean rectangular waveform swinging between nearly zero volts and nearly the battery voltage. Judging by the fact the inductors are only 150 nH (marked "R15") the frequency would be quite high - likely several hundred kHz, maybe 1 MHz or more.
@@d614gakadoug9 The frequency should be about 380 kHz as far as I remember. Quite a popular model for repair. Repairing laptops without an oscilloscope is repair at random.
Maybe GPU is not dead because this MOSFET is not a regular MOSFET. It is have a lot of internal logic components. Maybe it is also have some protection from short. It would be logical to put some protection function.
There are two FETs in the package, along with drivers and protection circuitry. The part is primarily intended for use in a buck converter, where one FET is used as the high-side switch and the other is used as a synchronous rectifier. If the rectifier FET fails short-circuit it protects the load from excessive voltage. The protection circuitry can detect overcurrent. I don't know without looking at the datasheet again if there is a FAULT output that can be used to shut down other devices. I'd be surprised if there isn't.
Yes. It is have protections: From datasheet: Catastrophic Fault Detection ♦ Thermal Flag (OTP) for Over−Temperature Condition ♦ Over−Current Protection FAULT (OCP) ♦ Under−Voltage Lockout (UVLO) on VCC and PVCC@@d614gakadoug9
Chips are usually rated for 10 secs hot air time to solder into place? Using low melt solder, could that chip be soldered a little quicker as you seem to have that hot air on for a very long time? i know the board is thick but..... You are brilliant and one of the best on you tube but that long cooking really rattled me!!
His desoldering and soldering methods are appallingly bad! Dealing with a part like that and the large copper areas is difficult. The appropriate way to deal with those issues to use additional heating, at a properly controller temperature, to be opposite side of the board. That can make a huge difference.
@@itnaklipse1669 Problem is unless you are very careful with heat, you end up stressing the chip out and it might work but lifespan will be shortened just as if you had overheated a CPU from dirty fans ect or too much current spiked through a part. The reflow machines have heating that will preheat the underside and use profiles to carefully heat at right temps and time so part is evenly soldered into place with min stress. You can do all this free hand, but you need to heat gradually then quick and then very important, slowly reduce temp so the part isnt thermal shocked as you remove heat. BGI is diff to reg soldering in that the balls YES you can solder them and it might work. BUT wrong heat and they form fractures and and other problems that will cause failures and so many tiny balls, you can see how just a couple play up and you have a big problem!! Except for this area, this channel and his skills are very very good and hes not "dodgey" in that he makes jokes and can do it bad or good but for laughs and entertainment, he uses little wires for fues which you CAN do if you know what you are doing. toot thick a wire and you have fire risk and damage and too thin and the wire might work for a little time but fail as it over heats over time and unhappy customer. his broad knowledge can fix boards where other "techs" cant but his chip soldering can be argued by some to be a little over long and hot, yet he gets the job done so........
@@itnaklipse1669you can drive over the speed limit a hundred times and not have an accident, but you can also have one the first time... The rules are the rules. Component manufacturers do tell you maximum time of heating at a certain max temperature. Of course you can choose to ignore them and get away with it. But why would you risk it? Why not use the proper tools and technique?
@@silviuguseila2552 when i drive, i make my own judgment when to speed or not, based on situation and experience. and i've now watched enough of Sorin's videos to trust his experience on electronics. 'rules are rules' is an axiom used by certain kinds of people - which is fine, but not everyone thinks so.
The comments about the thermal paste might refer to MSI "Phase Change Liquid Metal".. which is a compound that is solid metal when cold and turns liquid when hot. And it's absolutely rubbish 🗑.
There are two power MOSFETs and a fairly elaborate driver and control circuit. I very strongly suspect there are three separate chips in the package. In the electronics industry each would likely be called a "die." "Chip" is kind of a slang term.
Good grief! He doesn't even understand how batteries and their ratings work! The "five amps" marked on the battery isn't 5 amps. It is five ampere•hours. The battery can probably quite readily deliver 20 or 30 amperes.
Lenovo Legion/Legion PRO were/are one of the best cost/performance laptops available on the market. The screens on the PRO models are superb. You have no fucking clue what you're talking about buddy.
Worth adding that if you want to see not only if the power stage is working but also the quality of the signal it produces, you may check by using oscilloscope - probing on the coil that sits right behind the chip.
So glad you did the experiment with the thermal paste.
Sorin, great video as always, thank you for sharing. Paul, USA!
Bai Sorine, asta chiar a fost TARE !!! BRAVO !!! :D)))) era de asteptat dar nu n-am gandit... E cumva spiritual romanesc... E din categoria reparatiilor gen dresurile in loc de curea la alternator si oua in antigel cand ai radiatorul spart... Chiar ma-ntrebam odata de ce erau asa de multi romani renumiti peste hotare... si raspunsul: pentru gandirea neparametrizata, "outside the box" BRAVO!!! 👏
2:29 sorin dips the chip in rosin. 🐒
I was reading the datasheets when that video ended and didn't find the difference, but I think the reason why the GPU was still good is because of the catastrophic fault detection something-something that the datasheet claims it has.
Indeed, I work on GPUs a lot, and failed high-side MOSFET is about 1 in 5 chance GPU survived. When DRMOS is used, depending on the brand and quality of it the chance can rise to 3 in 5. So Sorin has outdated view on the subject really, he was so surprised the GPU was fine, when normally you do not make any assumption until checking.
I must add that short on VMEM / VCTRL rails are much worse then VCORE. Memory rails seems to be more delicate and even short detection is typically not fast enough to save the memory controller.
@@DIYRepairHour agree with you
One of the FETs in each package is used as a synchronous rectifier. If it fails short-circuit the load is protected from overvoltage. Presumably the FAULT output from the part is used to shut down the entire converter so other parts in the power path have a chance of survival. (one failed rectifier FET would short the entire multi-phase array through the winding of the inductor connected to the failed part)
How do you not melt the keyboard or plastic or any other object behind the motherboard. You do a great job.
I also wonder about that all the time
I did use hot air one on a laptop and bloody melted the keyboard.@@oilybrakes
Fav part of all Sorin videos is the end:
"We have pictuuuuure !" 😁
sorin i always love your vids they are amazing just 100 perfect wow what a great job as always this one was diffrent :D
So not a dodgy duck😂. Excellent video as always
Lucky customer, good job chief
Yeah the myth is that Lenovo Legion 5/7 etc 2022+ models use PTM7950 pads.
I went to lenovo forum and asked, the answer from Lenovo helpdesk was "normal thermal paste" but as to what type and brand no comment on that.
Personally i used recently NTH2, feels like it got hotter and doesnt boost as much as it was with the stock thermal paste (i did some benchmarks).
But just for the sake of the comment, in stress tests 12700h draws 130w for a second till it hits 100*C and throttles down to 109-112W and shits around 85-94*C, RTX 3070 draws 150w in full load and if numbers dont lie, ive seen 154watt with temps ranging 64-77*C.
Pretty good cooling, if you dont think about your laptop sounding like a drone and it might explode on your face or fly away at any momment....
Excellent work.Thanks.
It´s not thermal paste. It´s phase change material. It´s comes in sheets. Check mouser for "laird tpcm 7400" or "laird tpcm 5400". The one from lenovo is honeywell ptm 7950.
The new phase change material does not change to a liquid, but softens at about 55 to 60 C. Phase change material is a thermoplastic with thermal conductive fillers. Thermal paste is usually silicone oil or other oil with thermal conductive fillers.
If you replace the phase change on that laptop(I have the same one), the gpu will start overheating after a few months(the issue is more the hotspot), because there´s not good contact between the gpu and the heatsink, and the paste will pump out. That does not happen with the phase change material. And that´s why you see a bigger concentration of "paste" on one of the corners where the heatsink contacts the gpu.
For you to see the difference, it´s better to buy a phase change sheet and try it.
Bro, Sorin heated it up to 400+ degrees and there was no melting/liquifying of that.
Either the owner changed it to a regular thermal paste (which then dried up), or the laptop came from the factory with thermal paste instead of phase changing material.
Either way Sorin proved the point and I am sure he saw and he is aware of the existance of PMT from honeywell, but it is not the case here.
@@ElBandito_Gaming because it's old, if it passes the 2 year mark it will stay hard.
@@ElBandito_Gaming typical thermal paste will pump out within 2 or 3 weeks mark my words the customer will complain of heat related issues after using his laptop
😂
@@ElBandito_Gaming New phase change materials do not melt. They soften. They are thermoplastic based. The old phase change materials melted because they were paraffin based.
And if the paste reached anything close to 400ºC and he touched it, i can assure you that he would burn his finger instantly. Not to mention that the heatpipes would probably burst. Just because the air is coming at 400ºC from the nozzle, it does not mean that it heats everything to 400ºC instantly...
But hey, you are free to believe whatever you want to believe.
Bravo Sorin !!!! 👍🏻👍🏻👍🏻👍🏻👍🏻🥳
Interesting that the heatsink had pipes over the mosfets also, and the one that failed was at the end of that pipe, does that pipe have full contact with all the mosfets properly?
It should be Honeywell PTM 7950 phase change tim.
Please Reply:
Hi, I have the same laptop. My dedicated gpu is not working in devices manager it is show the yellow sign error"Device not connected properly." I checked the
board, and there are no shot circuits, but my Gpu has no heat up or anything.
Should I reflow my Gpu soldier, and how risky is it?
Good job mate 👏
Which thermal paste did you install?
Are these Legions break often? known to be one of the most reliable laptops
Sir cna i ask something what model of your thermal cam you used? thank you
Please, Sir can you tell us wich video was first? Because I'm lost....
where does it inject the voltage?
you should keep that sheet of padding for all your laptop repairs to protect the screen, just in case u drop a screw..
I see you you are getting more cheeky with old age. Hehe. Better than angry.
7:27 i notice that, becouse the previous video, the mossfet with less solder had more temperature conpared with this one that have soldero on it.
Thank you Chef !!
Lenovo Legion 5 15IM05H here. On thanksgiving 🦃 the Legion 5 shutdown unexpectedly. | order a new external battery and internal battery. Still not turning back on from the video this may be a mother board, CPU, GPU, issue? Not sure how it would have gotten damaged besides normal wear and tear? First time a motherboard went out on me. Any help from anyone on where I can go next for help would be greatly appreciated
Great video
S is for Sorin…
…S is for SMOOTH! 👌
I dont understand why no one yells CLEAR! when injecting voltage like in the ER that would be so cool... ;)
good video thankyou
Can’t you check with the oscilloscope if the phase is working? I have seen Northwestrepair doing it several times on gpus, I believe he’s probing before the inductor
The only correct way to check the operation of Drmos is with an oscilloscope. Then you will see if it works and if it works correctly. Are there any spikes or runts during operation.
People who really know how to use an oscilloscope and understand the circuitry they are working on tend to use a scope all the time. When I did repair work it was usually the first instrument I'd use.
Before the inductor is the right place. There would be a reasonably clean rectangular waveform swinging between nearly zero volts and nearly the battery voltage. Judging by the fact the inductors are only 150 nH (marked "R15") the frequency would be quite high - likely several hundred kHz, maybe 1 MHz or more.
@@d614gakadoug9 The frequency should be about 380 kHz as far as I remember. Quite a popular model for repair. Repairing laptops without an oscilloscope is repair at random.
thanks again
New youtube channel: D is for Dodgy 😅
i sure hope no chip has DD marking
APPARNTLY. the D version is rated upto 50Amps. IDK I cannot confirm
According to the original ON datasheets, both are "Capable of Average Currents up to 50 A"
@@d614gakadoug9 so sounds like is a dodgy chip lol
Ptm7950 Honeywell
nice job
Maybe GPU is not dead because this MOSFET is not a regular MOSFET. It is have a lot of internal logic components. Maybe it is also have some protection from short. It would be logical to put some protection function.
There are two FETs in the package, along with drivers and protection circuitry. The part is primarily intended for use in a buck converter, where one FET is used as the high-side switch and the other is used as a synchronous rectifier. If the rectifier FET fails short-circuit it protects the load from excessive voltage.
The protection circuitry can detect overcurrent. I don't know without looking at the datasheet again if there is a FAULT output that can be used to shut down other devices. I'd be surprised if there isn't.
Yes. It is have protections:
From datasheet:
Catastrophic Fault Detection
♦ Thermal Flag (OTP) for Over−Temperature Condition
♦ Over−Current Protection FAULT (OCP)
♦ Under−Voltage Lockout (UVLO) on VCC and PVCC@@d614gakadoug9
Chips are usually rated for 10 secs hot air time to solder into place? Using low melt solder, could that chip be soldered a little quicker as you seem to have that hot air on for a very long time? i know the board is thick but..... You are brilliant and one of the best on you tube but that long cooking really rattled me!!
His desoldering and soldering methods are appallingly bad!
Dealing with a part like that and the large copper areas is difficult. The appropriate way to deal with those issues to use additional heating, at a properly controller temperature, to be opposite side of the board. That can make a huge difference.
but what about the fact he doesn't break the components or have any problems?
@@itnaklipse1669 Problem is unless you are very careful with heat, you end up stressing the chip out and it might work but lifespan will be shortened just as if you had overheated a CPU from dirty fans ect or too much current spiked through a part. The reflow machines have heating that will preheat the underside and use profiles to carefully heat at right temps and time so part is evenly soldered into place with min stress. You can do all this free hand, but you need to heat gradually then quick and then very important, slowly reduce temp so the part isnt thermal shocked as you remove heat. BGI is diff to reg soldering in that the balls YES you can solder them and it might work. BUT wrong heat and they form fractures and and other problems that will cause failures and so many tiny balls, you can see how just a couple play up and you have a big problem!! Except for this area, this channel and his skills are very very good and hes not "dodgey" in that he makes jokes and can do it bad or good but for laughs and entertainment, he uses little wires for fues which you CAN do if you know what you are doing. toot thick a wire and you have fire risk and damage and too thin and the wire might work for a little time but fail as it over heats over time and unhappy customer. his broad knowledge can fix boards where other "techs" cant but his chip soldering can be argued by some to be a little over long and hot, yet he gets the job done so........
@@itnaklipse1669you can drive over the speed limit a hundred times and not have an accident, but you can also have one the first time...
The rules are the rules. Component manufacturers do tell you maximum time of heating at a certain max temperature.
Of course you can choose to ignore them and get away with it. But why would you risk it? Why not use the proper tools and technique?
@@silviuguseila2552 when i drive, i make my own judgment when to speed or not, based on situation and experience. and i've now watched enough of Sorin's videos to trust his experience on electronics. 'rules are rules' is an axiom used by certain kinds of people - which is fine, but not everyone thinks so.
Lenovo use Honeywell PTM7950 thermal paste.
they winding you up sorin with the thermal paste
I guess your hot air gun is useless or not calibrated.
We have a sugon-8610dx, 400C would ruin it.
👍👍
The comments about the thermal paste might refer to MSI "Phase Change Liquid Metal".. which is a compound that is solid metal when cold and turns liquid when hot. And it's absolutely rubbish 🗑.
The gpu-z test is no stress test for gpu stability. Furmark for 5mins would be enough for most cases.
A dat cineva un răspuns conform AI, diferența este de forma a procesoarelor, unul fiind mai mic
like and share his videos
So lenovo is using dodgy thermal paste, who could have thought that?
One Piece fans also wanna know what's the D :D
Hello🤝👍👍👍👍👏👏👏👏👏👋👋👋👋👋👋
Now you lost me. You said it’s a chip but you say it’s a MOSFET. Help me out here.
The chip is a mosfet.
There are two power MOSFETs and a fairly elaborate driver and control circuit. I very strongly suspect there are three separate chips in the package.
In the electronics industry each would likely be called a "die." "Chip" is kind of a slang term.
Good grief! He doesn't even understand how batteries and their ratings work!
The "five amps" marked on the battery isn't 5 amps. It is five ampere•hours. The battery can probably quite readily deliver 20 or 30 amperes.
D comes from duck -- lol
D is for Duck hahahaahha
i have picturrreeee!!!
Duck Lenovo is trash...so cheap plastic...and whole laptop is so soft...
Lenovo Legion/Legion PRO were/are one of the best cost/performance laptops available on the market. The screens on the PRO models are superb. You have no fucking clue what you're talking about buddy.
Nice one