Where is the heat?

[RMouse]

For the bulk of my folding, I used a Dell laptop with a Core2Duo processor, rated at 2.4 ghz. When this computer folds, it gets up to 90 C easily unless it is wintertime when part of my apartment is not heated. After it hits 90 C the CPU downclocks, first to 1.5 ghz, and then down to 0.8 ghz. This allows folding to continue albeit at a much slower rate. My MacBook Pro (with exact same CPU as my Dell), which I dont normally fold with, but tested it once, gets as hot as 110 C. It never downclocks so I shut it down manually then. That's just too hot for the long term.

Recently I got a new Dell laptop, running an i3 processor at 1.8 ghz. This computer is VERY surprising in that there is relatively NO heat given off during folding. Nor does it downclock. It ALWAYS runs flat out at 1.8 ghz. The temps max out at 60 C and this is *without* any major spool up of the fans. The laptop is as quiet as you can imagine. My other Dell would have the fan going full power, making all kinds of noise.

I'm amazed at how quiet and cool folding with this laptop it. It is a very cheap Dell laptop, nothing special. It cost at most $600.

Where is the heat when running 100%? How can I fold so much better (I get more PPD with this computer) and not generate so much heat?

Are i5's and i7's this cool too?

[Zagen30]

All of Intel's technology improvements over the last 6 or 7 years have resulted in a chip with many more transistors that consumes far less energy, and thus produces a lot less heat. I believe your C2D has a Thermal Design Power of 35W, while the chip in your new laptop, which I'm assuming is a Haswell, is rated for 15W. That's roughly 40% of the heat, though TDP is an inexact measurement; basically, it's what they think is a near-worst-case scenario. But your new laptop probably is generating less than half the heat of the old one.

There's a few major reasons why the new chip consumes less power:

1) Die size. C2Ds were made on either a 65 nm or 45 nm process, meaning the transistors were at most 65 or 45 nm long. Haswell uses the 22 nm process. As transistors get smaller, they use less power. Newer chips have more transistors total because you can pack more of them into the same space, but overall the trend at Intel has been less power overall.

2) Intel's FinFET transistors. These were first introduced in Ivy Bridge. Basically it's a 3-D, tri-gate transistor that greatly reduces leakage current and decreases the power needed to switch a transistor from off to on or on to off.

3) Lower frequency. 600 MHz is notably slower, and power scales linearly with frequency. It's a testament to the architectural improvements over the last several years that your processor can do more at 75% of the old one's operating speed.

4) Lower voltage. While this hasn't gone down as much over the years (1.25 V for C2D vs. 1.15 for Haswell), power increases with the square of the voltage, so that tenth of a volt is actually a bigger deal than you'd think.

[PantherX]

I am currently folding on i7-3840QM (Ivy Bridge) with SMP:5 and once I lock the CPU frequency at 2.8 GHz, my temperatures have been between 75C to 82C. With out locking the frequency, it would jump up to 3.4 GHz and the CPU temperature would be roughly 88C. Thus, I could lower my temperature by limiting the CPU frequency which suits my needs.

BTW, since my laptop's BIOS didn't allow changing the frequencies, I am using ThrottleStop (viewtopic.php?f=14&t=25336).

[RMouse]

Thanks for the feedback. I am impressed at the new laptop's folding power. I just broke into the top 4% of all folders based on rank. All with just two Dell laptops running 24x7.

[CBT]

When your computer is running extended times each day, over time dust will build up in the cooling system, particularly in laptops. You might want to use a can of compressed air to clean out the air vents on your old laptop, it can help a great deal.

[Adak]

It's a start for RMouse, but with 715 points, he is number 978,300 in the ranking of all folders, as of today's date.

With a total of 1,620,353 for all FAH folders, that puts his ranking at number 978,300, and thus in the top 60.38% of all FAH folders. Not bad at all for having folded 3 work units.

But that's nowhere NEAR the top 4% of all FAH folders. To get into the top 4% of all FAH folders, you have to beat this folder:

Code: Select all

Folding Name           points     work units   team #
Optimal_Karnage	     317913	  1396	      57858

4th percentile: 64,814 = .04 * 1,620,353

Which at 317,913 points, is a lot more difficult to reach.

[Jim Saunders]

Laptops: If there is a gap between the outlet of the fan and the radiator it can get packed up with grime, although getting to it usually isn't too bad. The heatsink could be poorly thermally bonded too. I had an Acer which melted the northbridge after the thermal pad bonding it to the CPU heatsink shrank and broke contact.

That said if it stays cool most of the time and only overheats while folding then it may simply be a marginal cooling system.

Jim