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I have a Lenovo y510p with a Core i7 4700MQ and SLI 750m. I believe that if a laptop is marketed with gaming or high performance in mind, the cooling solution should provide an option to keep everything running at max TDP. I can see having the default setting to be to throttle, but there should be an option to enable high fan speeds.

Flatland_Spider - That's very interesting. I'd love to figure out what is different between your setup and mine, the specs match exactly, but the output couldn't be more different.

I might have to investigate a little more deeply before I let Dell Depot have their way with my machine. Your report does seem to be in the minority, though.

Flatland_Spider wrote:

On my work issued Latitude E6540, I haven't been able to get the speed to drop below 2796.5MHz with the Windows High Performance power option.

This is using Prime95 with the In-place large FFTs using 8 threads. The laptop is on a wooden table, and the ambient temperature is at an indicted 69 degrees Fahrenheit.

Latitude E6540:
Intel Core i7 4800MQ 2.7GHz
16GB DDR3
Samsung SSD
AMD Radeon HD 8790M/Intel Graphics 4600

The Prime95 tests were run with Intel Graphics. I'll work on figuring out how to get the discrete card to be the only one running.

Edit: I was able to get it down to 2696.5MHz. I'll run it longer later. I'll also try to lift the laptop up to get more air flowing through the intake that is in the middle of the laptop.

Ok, pulled it out and retested. My experience is wildly different from yours. At idle, my CPU is hanging out around 2.4GHz with 1 core active, according to Intel XTU (not OCing, just using it for temps/voltages/etc monitoring). The very moment I fire off the standard large FFT/8 thread test, the CPU immediately drops to 1.9GHz, and within 30 seconds, we're over 75C and the clocks start dropping. We spend quite some time at 1.8, then when the machine passes 90C, we slowly but steadily drop to 800MHz, where we stay. The CPU continues to heat up till 98C, where it's at minimum clocks and voltages, so it starts doing the proper throttling, forcing idle cycles onto the CPU.

I guess I'll just see what Dell says in 2-3 weeks when they send it back.

This laptop was purchased around November/December of last year when Dell production was mostly idle. That might have something to do with it.

I'm using the CPU-Z, Monitor, and Intel XTU to get my numbers.

Idling on my wood desk:
Max: 3.596.5MHz
Actual: 799.2MHz
Temp: 126 degrees F

Start Prime95 Torture test (In-place Large FFTs 8 threads):
Max: 2796.5MHz
Actual: 2797MHz
Temp: 180 degrees F
Time: 9:41

Forge wrote:

Flatland_Spider - That's very interesting. I'd love to figure out what is different between your setup and mine, the specs match exactly, but the output couldn't be more different.

I might have to investigate a little more deeply before I let Dell Depot have their way with my machine. Your report does seem to be in the minority, though.

It could be missing thermal compound/pads. At very low utilization, things would look normal. Under normal load, things get out of hand real quick. It happens in our lab, from time to time, when we are testing out new cooling solutions. Heat sinks are swapped and someone gets distracted. As soon as we load up the card, the temps spike. It could also be a fault heat pipe that didn't get quite sealed or didn't get quite the right amount of "fluid".

While Flatland_Spider's system is a data point of one, it does lead one to think that it may be something specific to your system and not design issue. In defense of Dell, they are pretty good about specifying operating parameters of their systems and, within those parameters, their systems perform as expected -- at least in my experience.

--SS

I took a very careful, cautious look last night. Thermal compound is the thick grey slab all the OEMs seem to prefer right now. Seems well-enough applied.

Oddly, though, the bottom of the heatpipes looked... discolored? Braized? There were colors all over, almost looked like an oil spill, slight greens and purples and greys. The pipes themselves were clean, though the copper color was much darker than usual. I think the discoloration might be connected to the heat, and also explains why Dell painted all the user-visible parts of the cooling system flat black. If I'd seen the discoloration without getting farther into the machine than is normal, I'd say something.

I'm slowly turning this thread into talk about my particular laptop, though, which wasn't my intention. I really just wanted to talk about throttling in general, and figure out if I was being overly sensitive. I think the majority seem to feel that throttling against a workload, without some sort of internal or external provocation, is Not Good and should not happen, which matches my thinking originally.

Flatland_Spider wrote:

This laptop was purchased around November/December of last year when Dell production was mostly idle. That might have something to do with it.

Actually, mine would have been initially sold around early/mid December. Original owner returned it late December, Dell refurbed and resold it late January.

It really sounds like a poorly installed heatsink, or a bad fan.

Flatland_Spider wrote:

This laptop was purchased around November/December of last year when Dell production was mostly idle. That might have something to do with it.

I'm using the CPU-Z, Monitor, and Intel XTU to get my numbers.

Idling on my wood desk:
Max: 3.596.5MHz
Actual: 799.2MHz
Temp: 126 degrees F

Start Prime95 Torture test (In-place Large FFTs 8 threads):
Max: 2796.5MHz
Actual: 2797MHz
Temp: 180 degrees F
Time: 9:41

Time: 10:47
Max: 2696MHz
Actual: 2697MHZ
Temp: 199 degrees F

Forge wrote:

Thermal compound is the thick grey slab all the OEMs seem to prefer right now.

If it's thick, that's NOT good. Should be paper thin.

Flatland_Spider wrote:

It really sounds like a poorly installed heatsink, or a bad fan.

Agreed. I don't think it voids the warranty if you remove the HSF and re-apply TIM. Does the fan even spin up at those high temps? (TL;DR) Should be at/around 100% fan speed if you're throttling.

Maybe the heatpipes didn't get filled or sprung a leak, haha.

I'm not sure what would void the warranty. I've has Dell techs ask me to disassemble stuff to test things before, so I'm not sure where the line is.

Flatland_Spider wrote:

It really sounds like a poorly installed heatsink, or a bad fan.

Flatland_Spider wrote:

This laptop was purchased around November/December of last year when Dell production was mostly idle. That might have something to do with it.

I'm using the CPU-Z, Monitor, and Intel XTU to get my numbers.

Idling on my wood desk:
Max: 3.596.5MHz
Actual: 799.2MHz
Temp: 126 degrees F

Start Prime95 Torture test (In-place Large FFTs 8 threads):
Max: 2796.5MHz
Actual: 2797MHz
Temp: 180 degrees F
Time: 9:41

Time: 10:47
Max: 2696MHz
Actual: 2697MHZ
Temp: 199 degrees F

Time: 12:03
Max: 2696MHz
Actual: 2697MHz
Temp: 196 degree F
0% CPU Throttling

Edit: I raised the laptop 1.5" off of my desk with a couple of boxes I have, and the extra air flow helped. There was a significant bump when the laptop realized it had more airflow, but it settled down to the stats below.

Time: 12:12
Max: 2796MHz
Actual: 2797MHz
Temp: 194 degrees F
0% CPU Throttling

Ask for a Eurocom notebook

Flatland_Spider wrote:

I'm not sure what would void the warranty. I've has Dell techs ask me to disassemble stuff to test things before, so I'm not sure where the line is.

Flatland_Spider wrote:

It really sounds like a poorly installed heatsink, or a bad fan.

Flatland_Spider wrote:

This laptop was purchased around November/December of last year when Dell production was mostly idle. That might have something to do with it.

I'm using the CPU-Z, Monitor, and Intel XTU to get my numbers.

Idling on my wood desk:
Max: 3.596.5MHz
Actual: 799.2MHz
Temp: 126 degrees F

Start Prime95 Torture test (In-place Large FFTs 8 threads):
Max: 2796.5MHz
Actual: 2797MHz
Temp: 180 degrees F
Time: 9:41

Time: 10:47
Max: 2696MHz
Actual: 2697MHZ
Temp: 199 degrees F

Time: 12:03
Max: 2696MHz
Actual: 2697MHz
Temp: 196 degree F
0% CPU Throttling

Edit: I raised the laptop 1.5" off of my desk with a couple of boxes I have, and the extra air flow helped. There was a significant bump when the laptop realized it had more airflow, but it settled down to the stats below.

Time: 12:12
Max: 2796MHz
Actual: 2797MHz
Temp: 194 degrees F
0% CPU Throttling

Temperature and clockspeed have held steady. I'm shutting the test down.