Old thermal paste or airflow issue?

[Zm1TDkSnQkY4KEqskCARSBpk]

I've been trying to troubleshoot some performance issues on my laptop. Basically, after a while of watching youtube videos or playing games, my framerate will drop quite a lot (for example, 20fps to 2fps in Minecraft) and my CPU load will increase to 100% overall if it's not already there. I've noticed a correlation between this happening and my laptop being warm, so I checked my temperatures. Both my CPU and GPU are about 60 while idle, 75-80 during normal use, and 85-90 when gaming, although it takes a long time to get to 90. I got this information using lm-sensors, but my GPU driver configuration application consistently reports the GPU as being 3-5 degrees hotter than lm-sensors says it is, and I'm not sure which is more accurate. (Unless otherwise stated, all temperatures in this post are from lm-sensors.) When the bad performance starts happening, my keyboard and trackpad are noticeably warm, my left speaker grill is very warm, and the air blowing out of the side is uncomfortably hot. Despite this, both my CPU and GPU claim to not be throttling. /proc/cpuinfo reports the CPU sustaining base clock on all cores, and I don't think this CPU (i7-740QM) supports all core boost, and my GPU driver reports that the GPU is on the highest "performance level" from 0-2. However, I found that if I take the bottom panel off of my laptop and lift it off the table with two flash drives and a microsd card reader, the temperatures dropped (still 60 when idle, but now 60-70 during normal use and barely getting over 80 in games) and performance issues disappeared. This leaves me with a few questions.

 

• I thought throttling wasn't supposed to kick in until around 100 degrees, or is that just for CPUs?
• Is there a way to patch my GPU driver or firmware to let the GPU get hotter before throttling, and is this safe to do?
• If the issue seems to be more airflow related, does this mean that my previous suspicion that there was a problem with the thermal paste can now be dismissed, or is there a way to tell if that problem exists too?
• I want a more permanent solution than putting my laptop on flash drives everywhere I go. I'm thinking about gluing a couple layers of cardboard to the bottom (obviously not over the air intakes) to give it clearance. Will that be enough, or should I glue something thicker and more solid?
• Even at those temperatures, my BIOS isn't driving the fan quite as hard as I know it can go. (My BIOS drives it at about 3800 RPM, and I know it's capable of at least 4000 because if I stop my fan with my fingers, it will run at about 4000 RPM for a few seconds before dropping down to 3800 again.) Is there a way to fix that on Dell laptops? I don't want to cut the PWM wire because I still want variable fan speed and also don't know which one is the PWM wire, but I want to either fix the fan curve or have my OS control the fan so it gets driven at full power. Right now, if I write something to /sys/class/hwmon/hwmon1/pwm1, the fan jumps to the new speed, but then quickly jumps back to the old speed.

[Arttu89]

23 minutes ago, Zm1TDkSnQkY4KEqskCARSBpk said:

• I thought throttling wasn't supposed to kick in until around 100 degrees, or is that just for CPUs?
• Is there a way to patch my GPU driver or firmware to let the GPU get hotter before throttling, and is this safe to do?
• If the issue seems to be more airflow related, does this mean that my previous suspicion that there was a problem with the thermal paste can now be dismissed, or is there a way to tell if that problem exists too?
• I want a more permanent solution than putting my laptop on flash drives everywhere I go. I'm thinking about gluing a couple layers of cardboard to the bottom (obviously not over the air intakes) to give it clearance. Will that be enough, or should I glue something thicker and more solid?
• Even at those temperatures, my BIOS isn't driving the fan quite as hard as I know it can go. (My BIOS drives it at about 3800 RPM, and I know it's capable of at least 4000 because if I stop my fan with my fingers, it will run at about 4000 RPM for a few seconds before dropping down to 3800 again.) Is there a way to fix that on Dell laptops? I don't want to cut the PWM wire because I still want variable fan speed and also don't know which one is the PWM wire, but I want to either fix the fan curve or have my OS control the fan so it gets driven at full power. Right now, if I write something to /sys/class/hwmon/hwmon1/pwm1, the fan jumps to the new speed, but then quickly jumps back to the old speed.

1. Throttling kicks in as the temperature goes up, if it kicked in only after reaching 100C, it would be too late to prevent the CPU overheating and shutting down the machine.

2. Technically yes, but it would require some custom BIOS/driver setup, but I would say it's not advisable on a laptop, especially one this old. This is definitely NOT safe, unless you're an experienced overclocker and you know what you're doing.

3. Given how old that CPU is (i7-740QM was released back in Q32010), if you never changed the thermal paste, it won't hurt to change it. Thermal paste on a 9-10year old laptop won't be in great condition.

4. If replacing the laptop is not an option, I'd just buy a cheap cooling stand, gluing anything to the bottom of a laptop is not a smart solution to your problem.

5. Try checking on Dell's website if they still have any utility software for your laptop. If there's any way of permanently adjusting the fan curve it's gonna be in their software.

[Zm1TDkSnQkY4KEqskCARSBpk]

7 minutes ago, Arttu89 said:

If replacing the laptop is not an option, I'd just buy a cheap cooling stand, gluing anything to the bottom of a laptop is not a smart solution to your problem.

Technically, I could replace the laptop, but I'd rather not because this one isn't obsolete or too broken yet. I'll replace it when I go to college (I'm a high school junior now) because this one lasts like an hour to an hour and a half on it's current battery, and replacing it would be more cost effective and might even straight up cost less than buying enough batteries to power it all day. Zen 2 or 3 on mobile looks like it's going to be great, so at the very least I want to wait for that. What's wrong with gluing things to the bottom?

 

20 minutes ago, Arttu89 said:

Try checking on Dell's website if they still have any utility software for your laptop. If there's any way of permanently adjusting the fan curve it's gonna be in their software.

They don't have anything, but I found an unofficial package to disable BIOS fan control, and I was able to get my fan to 4850 RPM, which I think will help. Is it bad for my fan to run it over 1000 rpm faster than my BIOS drives it?

[Arttu89]

7 minutes ago, Zm1TDkSnQkY4KEqskCARSBpk said:

What's wrong with gluing things to the bottom?

Uhh, where to start:

1. Every laptop has vents on the bottom, in most cases those vents are either at the back or close to the back of the laptop and they need to stay open to provide proper air circulation to the components, sticking something to the bottom of the laptop might not work very well with the position of those vents.

2. Given how warm your laptop gets, glue on most common types of double-sided tape (assuming that's what you planned to glue it with) is gonna get soft and smear off as the whole thing heats up, and that glue is going to get on everything and everywhere and just make a giant mess of things.

3. It's just generally junkie AF and there are better cheap ways of doing this properly. I don't know where you're from, but in most countries you can easily get a perforated laptop stand somewhere in the 15-20USD price point.

 

21 minutes ago, Zm1TDkSnQkY4KEqskCARSBpk said:

They don't have anything, but I found an unofficial package to disable BIOS fan control, and I was able to get my fan to 4850 RPM, which I think will help. Is it bad for my fan to run it over 1000 rpm faster than my BIOS drives it?

I would assume they did that mainly for acoustics. If the fan is capable of running 1000rpm faster without any hardware modifications, then it's unlikely it would get damaged, because of that, but it might be uncomfortable to listen to for extended periods of time.

[Zm1TDkSnQkY4KEqskCARSBpk]

Yeah, I was intending to not glue where I know the vents ere, and I was planning on gluing with either a glue gun or epoxy. Duct tape and electrical tape were my backup plans if my parents weren't going to let me use the epoxy because I think we're out of glue sticks for the glue gun. I'm in the US, but $15-$20 is more than I want to spend, and most laptop stands I've seen lift the laptop way too much for it to be comfortable to use the keyboard. But I can go with that if I find one that's cheap enough and doesn't lift the laptop too much.

 

1 hour ago, Arttu89 said:

I would assume they did that mainly for acoustics. If the fan is capable of running 1000rpm faster without any hardware modifications, then it's unlikely it would get damaged, because of that, but it might be uncomfortable to listen to for extended periods of time.

Yeah, it is much louder and also makes my laptop vibrate noticeably. That might not be the best thing for the environments I use my laptop in, but it works.