Lets try to narrow down the Overheat issue. - HTC Rezound

Edit:
From what I have gathered from those that have provided info.
Around 120*F is normal for heavy use, around 105-110* for medium use, 100-105* for light use. This is with cell data enabled, wifi lowers temps 5-10*, also temps are for extended use scenarios. (over 10-15 min)
Heavy use= 3D game or graphically intensive 2D game, streaming videos especially HD
Medium use= basic games web surfing sites with lots of images or some flash content
Light use= sending SMS, basic fooling with settings or other basic functions, streaming music with the screen off
I think we need to get a bit more scientific about testing this overheating issue out. I need help from a large group of people. I need those who think they have overheat issues and those who do not for the info to be useful.
First off... I believe these temps are just the battery, not the CPU. I think the CPU is running relatively cool as the rest of the phone does not heat up, or it seems what heat is felt is coming from the battery only.
This would explain why people claim that the extended battery does not have this issue. As batteries with higher mAh ratings are able to handle the higher power demands with less heat.
We need to do comparison tests using the same apps across tests and the same use times as well. Also no over or under-clocking and using the same CPU governor. (and between everyone participating where possible)
I have Minecraft and Sleepy Jack, they both produce similar temps after 15 minutes of play time. (around 117-120*F) I do not know if it gets any hotter with longer use because I rarely play longer than that at a time. I am at about the same temp after only 10 minutes so maybe that is the highest it gets.
I know for certain that enabling WiFi has a big impact on the temps. My fiance's phone would only get about 95*F, (according to the SetCPU widget) but when LTE is enabled it would get to 115*F. Mine hits 105* on WiFi.
I want to do at least two tests.
Lets use the following steps to test:
-For all testing the test time will be 15 minutes of play time.
-Lets all use Minecraft since there is a free version and I know the app causes the phone to work hard.
-No over or under-clocking
-On Demand governor
Test 1) Airplane mode enabled
Test 2) 3G enabled (not everyone lives in a LTE area, if you do, data from LTE enabled would be useful as well)
Now some optional tests. I did some rudimentary testing and there seemed to be an impact on temps.
Optional 3) Using interactive governor or Lag free governor
Optional 4) Use a different kernel... If you are on stock switch to ziggy's and vice versa. (this may be the most promising test as since switching to ziggy's I have had a few lockups where the old Android logo pops up on the screen and I need to do a battery pull to fix it. This happens to the fiance's device as well)
If you do these tests, please post the results, and what ROM and kernel you are using. I will keep track of the results and update as appropriate.
Lets see if we can find some consistent data and narrow this heat issue down.
Edit:
Running Ziggy's kernel I hit 108*F kept playing and shortly after the phone did the odd crash I mentioned.

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Nice, had the same idea to do one of these over the weekend - you just beat me to it
I've done alot of research/ testing heat wise, and the pseudo-scientific conclusion that i've come to is that in a room temperature environment something like 75-85F idle & 110-115F netflix is normal for this gen of phones (Rezound, Galaxy Nexus, Galaxy S II, etc) - Give or take another 5F if you're using 4G. Seems like some devices are luckier than others & stay slightly cooler, but i'd gauge that they aren't the typical use case. IMO, (along side battery) data is a huge reason we've seen some of the face melting temperatures people have been reporting.
One thing I think would really help this thread is to set an easy to follow format for posting results. For example, here's a few tests I've done:
### Phone Info ###
ROM - Stock
Kernal - Stock
CPU Speed - Default (1.5)
Battery Type - Standard
Case - Generic TPU
## Test 1 ##
Charging - No
Data - 4G (4 bars)
App - Field Runners
Test Duration - 15 min
Start battery temp - 85 F
End battery temp - 112 F
Total Battery Drain - 20%
## Test 2 ##
Charging - No
Data - 4G (4 bars)
App - YouTube
Test Duration - 20 min
Start battery temp - 85 F
End battery temp - 104 F
Total Battery Drain - 16%
## Test 3 ##
Charging - No
Data - 4G (4 bars)
App - Onlive
Test Duration - 30 min
Start battery temp - 85 F
End battery temp - 125 F
Total Battery Drain - 40%
Hope this helps, i'd really like to see people participate - this information will be helpful for pretty much everyone in the Android community with a current gen phone.

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Stock rom
Extended battery
Charging - yes
App - shine runner
Duration - 20 min
Start temp - 96F
End temp - 115F
3g, 3bars
This extended battery will get just as hot as the stock, just takes a little longer.
Edit-not quite as hot as the stock, but pretty toasty.

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if it's the battery, then isn't the only parameter we need to test is current draw from the battery? no matter what radios/apps are enabled/disabled. It's bottom line is, the more we're drawing off the battery the hotter it's getting? I'd have to bring a pro in here on how Li-ion works in this form factor and why it gets hot, or what corners the battery manufacturer cut to make it possible!

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The only time my battery gets hot is when I am in a weak signal area and the phone is searching for the 3G-4G signal. During daily use in a good signal area it never heats up.

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My phone (and wife's also) heats up most notably during charging, especially when the battery is around 99% and going 100%. Usually the temp goes to ~ 45C (115F). In some rare cases, it was too hot to touch (dunno the exact temp). But some other times it would stay cool at all time.
Wife's first phone went into bootloop and her current phone is a new replacement. I kind of believe the overheating was the main cause of the bootloop problem.

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thatsricci said:
if it's the battery, then isn't the only parameter we need to test is current draw from the battery? no matter what radios/apps are enabled/disabled. It's bottom line is, the more we're drawing off the battery the hotter it's getting? I'd have to bring a pro in here on how Li-ion works in this form factor and why it gets hot, or what corners the battery manufacturer cut to make it possible!
Click to expand...
Click to collapse
It's more than just the battery. Also: feel free to post a test - the more data we get from everyone, the better.

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One important variable missing: ambient temp.

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I was just playing words with friends for ten minutes:
Ambient temp: 67, Screen brightness: 50%,
4g: ON
wifi: OFF
my temp went to 105F, it's NEVER gone to 105F when playing before... and I play it every evening. It was hooked to the USB charger at the time, and when I felt it getting so hot, I looked at battery monitor and my net charge was negative, so it was using more than it was charging off the usb...
maybe something in some of those apps triggers something that causes the temp to rise? a loop? something?

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thatsricci said:
I was just playing words with friends for ten minutes:
Ambient temp: 67, Screen brightness: 50%,
4g: ON
wifi: OFF
my temp went to 105F, it's NEVER gone to 105F when playing before... and I play it every evening. It was hooked to the USB charger at the time, and when I felt it getting so hot, I looked at battery monitor and my net charge was negative, so it was using more than it was charging off the usb...
maybe something in some of those apps triggers something that causes the temp to rise? a loop? something?
Click to expand...
Click to collapse
I noticed any time I charge with USB and use my phone it gets hot
Sent from my HTC Rezound

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dustintheweb;21090574
One thing I think would really help this thread is to set an easy to follow format for posting results. For example said:
Good layout... and I think you are right about 115-120 degrees is normal for heavy use with apps that really stress the CPU or radio.
thatsricci said:
if it's the battery, then isn't the only parameter we need to test is current draw from the battery? no matter what radios/apps are enabled/disabled. It's bottom line is, the more we're drawing off the battery the hotter it's getting? I'd have to bring a pro in here on how Li-ion works in this form factor and why it gets hot, or what corners the battery manufacturer cut to make it possible!
Click to expand...
Click to collapse
A pro huh... good thing I'm here.
Ok I'm not a "pro" as it were, but i know a thing or too.
Its not going to be simply the battery, but I think it is a big culprit, and most of these devices only provide battery temps, not CPU or internal temps, this limits our overall knowledge of what is going on internally. The battery getting hot causes the device to heat up as well so a bad battery that overheats can cause the device to overheat.
All batteries will convert some energy draw into heat. This is caused by the internal resistance of the battery. Li Ion batteries have fairly low internal resistance compared to other types, but battery design an affect power output handling. Pulling more power than the battery can handle or near its limit and you get more heat than normal. The heat to output ratio stops being proportional and becomes exponential. So that means the real kicker is the actual amp draw on the battery. How much power the battery can handle is related to both the capacity of the battery and the manufacturing process/ design of the battery construction. I bet the new devices are straining the battery more than the current design can handle. There are better battery manufacture processes for better power handling, but that increases the cost of the battery.
(BTW battery is a misnomer for these, they are cells, specifically one 3.7/8V Li Ion cell. The difference is that batteries are made up of 2 or more cells. This goes for AAA, AA, C and D cells as well. Car batteries for example are made of six 2V cells, 6V lantern batteries are made of four 1.5V cells and 9V batteries are six 1.5V cells)
This is one reason I want to do a test with airplane mode on. This helps lower the power draw and allows us to get a better overall device temp, this helps us know if there is an issue with the CPU getting excessively hot vs just the battery being stressed to hard.
Kane5581 said:
One important variable missing: ambient temp.
Click to expand...
Click to collapse
I assumed most testing would be done at room temps of 68-72 degrees. If anyone tests in temps that are much higher or lower, then that would throw off the measurements.
I switched back to stock kernel, going to check for lockups and issues like I had before.
Click to expand...
Click to collapse

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nev310 said:
I noticed any time I charge with USB and use my phone it gets hot
Sent from my HTC Rezound
Click to expand...
Click to collapse
Charging always causes heat. You are forcing power into a small space.
Charging via USB should only get the battery a little warm to the touch. 95* or so at most.
Charging with AC should get it a few degrees higher. I would think over 100* is odd.
as you reach 100% is when the heat should spike to the max temps I mentioned, before that it should just be warmish.
I will check mine to see how it behaves, but all my R/C batteries behave that way.

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Replacing the kernel with stock lowered my temps quite a bit. I was around 110-115 degrees after 30 minutes or so. This was with LTE enabled.

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Nobody else have anything?

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noticed most of my heating issues when 4g was on (even when idling on 4g). Leaving in wifi and 3g keep the stock battery cool...on the extended I never really notice the heat, even on 4g.

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I realize that you're trying to keep things as similar as possible, but I had an issue today listening to the broncos game in the NFL app while charging. It got so hot it boot looped. After getting it back up and running I started monitoring battery temps and even with the screen off and just listening to the game, it would get extremely hot. Btw, I have 4G 4 bars. A couple of times I ran to the freezer and put the phone in it for a couple minutes to cool it down as the temps got above 117°F.
From here, I thought it might be the CPU, so I set the maximum setting to 384 in antutu and then let the phone sit there with the screen off just as before listening to the game and still charging. Same thing, phone got extremely hot, 115°F. Although, what I find strange, is I can watch Netflix while charging and even tho it gets warm, it never gets above 115°F and never goes into the boot loop issue. Same exact location, charger, ambient temps, signal, the works. So I'm wondering if an app is just poorly written and causes some sort of excessive use of the radio.
On another note, I had a rezound battery in my thunderbolt and never had any issues what so ever with heat.
Sent from my ADR6425LVW using Tapatalk

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What temperatures are you people expecting to see just out of curiousity? I mean if we run 3d intensive apps, videos, extreme web browsing we're going to see high temps since we are stressing the devices. We do have to remember these are compact devices and they are limited to what type of heatsinks/cooling they can add. From the multiple posts form this thread and others like it, we can see the majority of our devices run at same temps while under load. If it hasn't already been done maybe we should contact HTC and see what they say? Just a thought.

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zetsumeikuro said:
What temperatures are you people expecting to see just out of curiousity? I mean if we run 3d intensive apps, videos, extreme web browsing we're going to see high temps since we are stressing the devices. We do have to remember these are compact devices and they are limited to what type of heatsinks/cooling they can add. From the multiple posts form this thread and others like it, we can see the majority of our devices run at same temps while under load. If it hasn't already been done maybe we should contact HTC and see what they say? Just a thought.
Click to expand...
Click to collapse
I am trying to find the norms and what is too hot.
I am thinking 115 is normal for heavy use. But we need to be sure, if someone says they only hit 100 under similar conditions as someone that hits 120. it may be that 120 is a problem temp and that 100 is normal. It may also be that the person only hitting 100 is just lucky.
tbot said:
I realize that you're trying to keep things as similar as possible, but I had an issue today listening to the broncos game in the NFL app while charging. It got so hot it boot looped. After getting it back up and running I started monitoring battery temps and even with the screen off and just listening to the game, it would get extremely hot. Btw, I have 4G 4 bars. A couple of times I ran to the freezer and put the phone in it for a couple minutes to cool it down as the temps got above 117°F.
From here, I thought it might be the CPU, so I set the maximum setting to 384 in antutu and then let the phone sit there with the screen off just as before listening to the game and still charging. Same thing, phone got extremely hot, 115°F. Although, what I find strange, is I can watch Netflix while charging and even tho it gets warm, it never gets above 115°F and never goes into the boot loop issue. Same exact location, charger, ambient temps, signal, the works. So I'm wondering if an app is just poorly written and causes some sort of excessive use of the radio.
On another note, I had a rezound battery in my thunderbolt and never had any issues what so ever with heat.
Sent from my ADR6425LVW using Tapatalk
Click to expand...
Click to collapse
Go play an app that is heavy in 3D, lets see what temps you get. If you go much over 120 it may be an issue.

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Running Gun Bros for about 20 minutes gets me up to about 105°F. Right now after the phone had been sitting for 5ish hours doing nothing its at 98°F.
Sent from my ADR6425LVW using Tapatalk

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I think it is Ziggy's kernel I have never got 125f when tethering for 30min or playing GTA for 30 min. I am going to try another kernel.