yashsingh1/xdaforums huggingface dataset:
[HD2 General] motoi_bogdan:
please be a little more explicit.

as i understand, after making this intervention, the device still didn't work but the manifestation of the problem changed?

If i get it right and from what i know already, you improved the cooling but for some reason it was not enough. Phone locking or 7 vibrates in a row is worse then simply restarting as i experienced on mine's. Example : if i tried to induce the problem at the start of my experiment, i wound notice first that the phone would start to restart itself, then after 4-5 restarts in a row i would end up with the phone locked either at start-up or in an application.

Also, if the problem damaged the BGA connections severely and has progressed beyond a certain point, simply cooling up the cpu won't suffice as the damage to the BGA connection is still there and already done. In that case only reheating could help but again, that carries the risk of destroying the BGA soldering if done improperly or simply if you aren't lucky.

At first, try to lower the temperature at witch you experiment with your phone. Say.. 10 degrees lower then now, does it still restarts? 20 degrees (in the freezer) does the problem still happens?

This will show you how close/or how far you are from a temperature that the phone in it's current condition can handle.
[HD2 General] januszgorlewski:
I've done mine exactly as you described but without mica foil, just aluminium sheet and thermal paste.

no go for me but i am not professional, so anyone should be lucky i guess?

was restarting at 35degrees, now at 32.5
[HD2 General] motoi_bogdan:
i'm sorry to hear that. it's true that having seen various thermal designs i got some sort of feeling about how things should work. However if the temperature limit needed to induce the problems has now fallen to 32.5 it seems you somewhat worsen then heat transfer from the chipset to the cooling system.

One more word, the problem isn't related to a thermistor unit inside the cpu, telling it to restart at either 35-40 degrees or such sort of values. From most CPU datasheets i've read, most semiconductor made devices should take up at least 75-80 degrees without ANY damage to themselves. desktop sized cpu's, simple transistors on other similar equipment can withstand 105 degrees core temperature without silicon oxidation ocuring.

I only wish to state another thing. You aren't actually trying to cool down the cpu, you're trying to cool down the soldering between it and the board. The cpu can take the heat, the board is designed to take the heat, but the soldering is the weak point here. When temperature increases those small BGA balls tend to dilatate and break electric contact. That's the real problem. I can't dismiss the effects of heating the cpu with a solder station (although it didn't solved my problem by it alone, it surely ameliorate the temperature threshold at witch the restarts/freezes are ocuring).

Pressure is also relevant, although it doesn't seem obvious in my pictures, there's quite a big amount of pressure on the cpu&board because of this cooling system and the mica pads (i still consider them essential to this design - heat transfer is waaay better then thermal paste or aluminum.. they are simply made for this).

Pressure can force the BGA soldering to stay in position, there is a chance, not sure about this but it can contribute. Also... it took me about 3 hours of tweaking with the positioning and pressure aplied by these materials in order to finally get to that specific configuration. Most tests were made with the motherboard exposed and temperature was measured directly at the board level.

Don't give up but never stop to work carefully when dealing with components, the motherboard and such sensible things.

At worst, if this fails completely and i was just a lucky example, this will provide some prof of serious hardware failures and bad design from HTC to this phone. Also, for those who are trying such procedures, try to document what you are doing (pictures, measurements), it will be easy to understand these problems and their real cause. I supose i will also have to disassemble mine, because... well.. i did use some crappy thermal paste and the thing is like pouring out from the back of the unit, lost it's consistency and looks pretty weird. I'm sure that the guts of the cooling "system" will still work fine but... it looks ugly to see something oily around the battery compartment. :D (used industrial level thermal paste)
[HD2 General] abufaris:
first i should thank u for great job,and my story started with my hd2 when the gps signal gone away,i always using igo8 and it was normally since i noticed that the phone has no gps signal,,,,start to change the rom, but the same,after that i went to load wp7 roms into device,and, the heat broblem started with,the device start to be hot and hot,freezing ,then i back to win mo 6.5 ,with the same issue,i did the whole steps of ur thread,i can feel the heat come from back of the device,even i put some thermal grease with meca foil to the back,but the same,

any way i used a TYTN2 (kaiser) for three years without facing any troubles like that,HTC should bee responsible for here job,`HD2 was like a dream for me to have,and i pay for around 800 dollars, because we dont have here any HTC dealer,only black market,my money now gone with the wind,the phone become like a toy,only receiving calls,no gps,no application,even no more games :)

i send HTC company a letter and they said u should send it to us by mail to the HTC global,and the will examin it,if need any repairing i should pay money for,****...

any way the only solution for me is keep looking around the internet for some solutions for my problem,and i think i am not alone here,

is there any possibility to place tiny fan :) i know u will laugh now,but its an idea

thank u :)
[HD2 General] harrrysekhon:
sir my hd2 restarts at 32.5 degres...do i need to do the 3rd optional step ?? I hav never done such thng b4 ... I hav made available evrythng excpt mica crystal pads because i live in a village in india so stuck at this step..!
[HD2 General] motoi_bogdan:
@harrrysekhon well, your phone is almost as worst as mine's before the procedure. Mine was also restarting around 30-32 degrees so.. no navigation, no video playback, no intesive apps&games no nothing.

Before even thinking about reheating, check the following.

There is a distance between the cpu chip and the metal shield above it. They don't come in to contact by default. That distance MUST be filled, therefore i used the mica pads i was talking. What did you used in your case?

Please take note that this is the most important step in this setup. Heat must be taken away from the cpu, the job must be done effectively. On my first testings, if the mica pads weren't in good thermal contact with both cpu and metal shield, the thermal performance of the cpu actually got worse or remained the same (still restarting). I did the testing with the phone's case opened.

Great care must be placed in that area, i have not tested anything but mica pads for i know they are best suited for this purpose.

Also a fair amount of pressure must exist between the display's back, the cooling system and the motherboard. This will allow a good contact between the various elements of the cooling system. Too much pressure isn't good however, as you risk either breaking the display or making it more vulnerable to break in the event of a mechanic shock.
[HD2 General] mmaiolo81:
Great job compiling this info... I have hangs and reboots with the 7 vibrates of death at about 31-33, got it damaged, second hand also, I am going to try your 'heatsink' idea this week... I will report back when I attempt it...

found some tp-220 mica pads on mcmelectronics.com ordering in the am....
[HD2 General] motoi_bogdan:
i first thought of this as a last resort option for HD2.

The normal procedure would be to de-solder the qualcomm chip and reball it, then re-solder it back. This is kind of impossible because there is no BGA former for this chip in order to place the solder balls on it. Furthermore... there is that resin that prevents removing the chip as it melts at a higher temperature then that of the solder joints. If the chip would be heated at that level it would most probably die out from overheating.

So, with a motherboard replacement as the single most viable option, i had nothing to loose when i first attempted this "mood" (i could not use a phone that cannot work at 25-30 degrees ambient temp).

This procedure includes some experiments, proper placement of materials, it's a bit trial and error. Once it was done, it saved my phone, but as being the single example of this working, i can only state that results can vary.

Try to apply some sort of pressure between the cpu, it's metallic shield, the custom made cooling system and the back of the display. All those components must be in perfect contact from a heat transfer point of view. Pressure is almost as important as the cooling system itself, but too much of it can be dangerous for the display - you have something hard pressing on the back of it, thus making it more sensible to outside pressure (more likely to break in case of impact or some mechanical shocks). In my case, if i make a heavy push on the buttons, there are some color spots that appear on the display suggesting pressure is being made on that area. The spots aren't permanent and i never push hd2's buttons that hard - to make those things visible, so it's not a problem on it's self. But it's an indicator on how tight things are inside there :)

Good luck and i'm hopping for good results.
[HD2 General] mmaiolo81:
Yeah it is a last resort option for me also... I can't even make it 8 or 9 hours, of just texting use without it hitting a freezer... so if this doesn't work, new main board here I come... but this is a cheaper option, so I might as well start there... also I have an otterbox case, so not super worried about mechanical shock... I will order the mica sheets this evening... then just to wait for them to come in... also thank you for your time and effort... it is worth a shot....
[HD2 General] harrrysekhon:
sir i found out a person who says there is a process called reballing and resoldering the qualcom chip which u are talking about...he says tht the process wil b done with a laser gun...is it possible sir n should i give him the phone for this?
[HD2 General] jotekman:
Speaking about the same subject but with a slightly different vein, I had a laptop, HP, which the GPU was overheating and causing a black screen. Took it apart, cleaned everything, took off the thermal pad between the GPU and heatsink, put in a polished copper penny with Artic Silver #5 thermal paste on it, put it back together, and no more black screens. Concept is the same I would think.

One could also use the thermal paste with crushed synthetic diamond in it. Better conductivity.

On the other hand, while the Mica sheets are good, are they as thermally conductive as, for example, 100% copper?

One thing which may have helped, though, is if the solder points are cracking, putting your heatsink in there may be pressing a bit on the cpu, pressing the chip into place more and keeping the point contacts more stable, thereby allowing you to run a little bit better. Though perhaps forcing it against the screen, like you said, could eventually cause problems. Could another solution be found? Is it possible, for example, to make a layer which would connect somehow to the aluminum back, making for better heat dissipation?
[HD2 General] HillsRider:
I have an Incredible that is suffering the same symptoms. At least I have a few ideas to try now. Thanks for sharing your experience!
[HD2 General] Chaosstorm:
Interesting read, as ive just placed a bed on a hd2 :P

This reminds me of geforce 7/8/9 series cards that you can rebake in the oven at 200c for 10 minutes. Ive baked already a 7900GS and a 8600m GT both worked again after, before i baked them they woudnt give any screen at bootup or hang directly.

Woud this maybe work also the same way for hd2?

As for the desktop gpu's I haven't placed any voil or something over the other components.
[HD2 General] motoi_bogdan:
yep, did my time baking different chips back when i didn't had the equipment to properly preheat a chip before the main heating sequence.

By the way i stopped working in a service center for some years. But being passionate on electronics i never miss out a chance to poke around with my gadgets :)

Once, i've placed one piece of laptop motherboard, containing the gpu chip inside an oven to preheat it, but forgot it for to much time. When i realised the mistake i rushed in, removed the board and after it cooled down i placed it back on the motherboard to see if it killed it, but surprise - the board was fine - even the original problem disappeared. It was some old ati chip from some ibm lapop. Those were early times, one of the first experiences using heat on these chips.

However i don't recommend this on hd2's board. The reason, the display connector. It contains some plastic parts, so if heated, although those parts are supposed to be heat resistant they can bend/deform so the connector won't make proper contact to the display's ribbon like cable. Localized heating remains the "safest" solution for hd2 ..if you're willing to take the risk.

I would avoid heating a phone board without having some relevant back experience. They're quite different from laptop boards. Tolerances are smaller, chips are smaller so the BG array is smaller also, risk for damage is greater. I have heard of people heating GPU's with butane torches, heat guns.. you name it.. but not on phones :D

Heating some chip to 360 degrees, poking around with it and not killing it, takes some experience, a steady hand and some common sense. I sincerely don't know whats happening under a chip that i heat or try to de-solder, but some little birds in my head whisper to me that it's done and the chip is ready to be removed. I cannot explain it. But at first, those little birds needed some tuning. I have a P2 laptop CPU placed on my key chain. It's a nifty and geeky thing, most people see it like that... i see it as a bad reballing experiment back in the days... :D

... but it indeed looks nice
[HD2 General] Chaosstorm:
I know someone who fixed a gpu even with a lighter :).

Might that be possible too on this chip? since the heat goes directly on the chip and doesnt spread like in the oven.

He heated it up for 1 minute with a lighter and did put on some thermal paste and it worked fine after..

When my HD2 ever breaksdown I'll try it with a lighter first and post the results here.
[HD2 General] DooDle78:
I personaly though of an overheating issue, but did not go that far... yet.

I was more trying to get the CPU speed lowered instead...

I'll probably do a bit'o'both! ;)

Thanks for sharing this!
[HD2 General] mmaiolo81:
I've tried underclocking down to 7 something and still have the issues, probably doesn't help that it is already 30c in florida... only leaves me 2.5c before it needs me meet Mr. Freeze all... still waiting on my mica chips from MCM electronics...

Edit: UPS says mica chips should be here friday...
[HD2 General] mmaiolo81:
Well the stuff came in for the heat sink... made it... put it back together VERY carefully... still has the thermal issue as I can't get it to boot without the freezer, and digitizer and bottom keys stopped responding...
[HD2 General] motoi_bogdan:
sorry to hear that.

The touchpanel and the hard buttons are linked to the motherboard via a ribbon like connector (touchpanel via the display ribbon, buttons via separate ribbon). Thermal grease is electrically insulant. So if some of the stuff got on those connectors, the small contacts that need to be done when securing the ribbons inside the connectors won't be properly made - hence your problem. You should try to get those cleaned if any paste got inside (or on the ribbon connectors).

Also, please note that the aluminum foil must not touch the components on the motherboard, except the metallic shield over the cpu area. If it touches the components you may have a short circuit over there, if it touches the edge of the "digitizer's" glass you can have serious electromagnetic interferance, thus preventing the touchscreen to record variances in electric capacitance that occur when you tap it.

Your failure to resolve the problem, may prove that reheating the cpu itself had some influence in the end. The conclusion may be actually quite logical. If the cpu.. let's say, restarts at 32 degrees, when the phone is kept in the sun the whole thing should be above 32 degrees, so you couldn't boot the phone. Simply adding a piece of metal over the cpu won't actively cool it down, if we imagine the above scenario, that piece of metal will simply heat up with the rest of the phone in the summer sun so it couldn't actually solve the problem by it's own. CPU will still restart at the same temperature threshold.

So, we can assume reheating the cpu did actually made a difference in my case. By reheating it i was then able to increase the minimum temperature threshold required for the cpu to restart on it's own. In my case it didn't solve the problem on it's own but coupled with the cooling system it produced the desired effect.

So i guess in the end this will no longer be possible as a DIY fix, as it will most probably require reheating using specialised equipment (not everybody has a smd rework station.. i guess). If the effects of a custom made cooling system are so some extent reversible (you can't simply take it off) a badly made reheating will kill the cpu and leave you with no joy. But i guess that's the only thing remaining as a possible solution and as i did it, i was simply lucky.

Again, sorry to hear you still have problems with the phone :(
[HD2 General] mmaiolo81:
It was my fault, I opened it... I opened it again to check on the aluminum, and past issues you mentioned... there was some past on the chip on the back of the LCM, but none on the 'edge' of the digitizer. When I went back to put it all together, I noticed I forgot to take off the mini flex cable that I think goes to the buttons... well it's torn now... I'm not spending anymore money on this thing, I'm just going to get a different one... Thank you for your help
[HD2 General] youngdaddytc:
first of all, nice job in figuring this out. im really surprised that these manufacturers would design a processor that allows for a pocket of hot air to sit around it like that.

i've fixed many computers over the years. recent ones all have heatsinks with fans that blow that air away. and there's ALWAYS a way to dissipate the heat away from the processor. even my laptop i have now, is designed so that the keyboard itself is part of the heatsink so the heat is more spread out.

i had just assumed up to this point that cell phone manufacturers would have taken this previous knowledge and applied it, making a better product. and to be honest im really surprised they haven't.

i read through the whole post and saw one guy mentioning a copper penny. the first heat sinks i dealt with in the early 90's on some on pentium 1's (with the ability to onboard overclock from 133 to 233 MHZ woohoo) had just a copper heatsink placed on top WITHOUT a fan. then of course we graduated to faster processors and had to use different materials and fans to get rid of all that temperature buildup. but the principle was the same, make sure that processor isn't getting stuck heating up.

anyway, i may have to try some of these methods as my phone is starting to exhibit the same problems. thanks for the ideas and all the research.
[HD2 General] januszgorlewski:
@facdemol

would you like to have my hd2?

:) i've lost my patience over the time, insurance people are crap, and as you may remember or read back, i've done some job with mine, tried to go good, but nothing, device itself is working you can call as long as you wish, but when it comes to playing with the phone- goes dead(reboot) in 1-5min.

can supply a box with all the accessories received on purchase.

(i cant pm you for some reason)pm me if you are interested with it. without the accessories will be ok, but still with the box.

will reply asap, i am checking this website every 2-3days

P.S.:i know it's not a marketplace, forgive me, but these days scammers are all over marketplaces...:(
[HD2 General] yurigagarin61:
1 GHZ is enough for me :D
[HD2 General] nicolas.k:
Touch Screen that makes poor contact

Hello XdaMens,

I have a problem with the Touch Screen that makes poor contact at the location of the connection between CI & Screen since yesterday (ahggrrrr, I love too much it).

But, despite the four screws unscrewed but I can't to remove the case. Could you explain us without breaking of course because it still works at 50% ?

Many thanks,

Nicolas
[HD2 General] motoi_bogdan:
i guess that you're trying to dismantle the phone and although you removed the screws, the casing still doesn't come off. You need to use some plastic tool to pry open the outer case from the display unit. try this guide:

http://pocketnow.com/hardware-1/official-htc-hd2-disassembly-assembly-training-videos-leaked

Also, about HD2 restarting or vibrating or whatever thermal related problems, i will update this topic once januszgorlewski's hd2 arrive and i can continue testing.
[HD2 General] Marky909:
The last couple of months i had restarts and freezes too, and decide to return the phone back to HTC (although the digitizer was cracked), because it's only 9 months old. Last week they analysed it and quoted me 480 euro's !!!! :mad: because the devices was damaged and therefore warranty was void! The only thing is that the digitizer was cracked long time before the freezes start.

Anyway, after a few dissapointing phonecalls with HTC, i decided to let them return my phone an maybe take a look at it myself, when i came upon this thread.

The symptoms are as you describe in stage 2. Never had 7 vibrates at boot, but anoying enough. Playing Angry birds for example for 10 minutes surely gives me a freeze.

When i get my phone back, i will try the heat dissipation fix, maybe it will be a fix if the device is only in stage 2.

I'll keep you posted.
[HD2 General] BACDAR:
Hi, I'm new. It's a nice post. Loking for the best rom end more estable for android in hd2 leo.

Any sugestions?
[HD2 General] nicolas.k:
Excellent with two videos 'Assembling & Disassembling' HD2 and it's parfait for me. :):):)

Nicolas
[HD2 General] atjong1:
My HD2 freezes in these conditions:

1. room temperatures of 22 degrees C (72 F) or above AND

2. charging (car charger) AND

3. navigation software running AND

4. screen brightness set to high.

The lower back of the HD2 feels warm when it freezes. Rebooting usually works but if I don't eliminate some of the parameters above it will soon freeze again. Shielding it from the sun in the car seems to help postpone freezing. Having more CPU intensive software like a music player running causes this problem to occur sooner.

I would like to try making a heat sink to so I'll be monitoring your progress curiously. I hope the conclusion won't be that the soldering is faulty because I can't fix that like you did. If that's the case then I guess then the only thing that could save me on long holiday trips is mounting a small fan in my car blowing air over the HD2 :-). Keep up the good work Facdemol!