Series 9 question - how does Silent Mode work?

Hey guys,

Just got my Series 9 900X3A-B06US and it's fantastic. One question though. I love using "Silent Mode", which kills the fans and allows me to work and watch movies in peace and quiet, but I have no idea how it achieves its goal.

I'm worried it's a) downclocking the processor/graphics card massively and severely hampering performance potential or b) raising the temperature thresholds to dangerously high levels.

Has anyone figured out how this works yet?

Cheers,

mj

 

It may be a bit of both.

Use HWiNFO to figure out what is happening. It has a good display of CPU speed and if you enable Sensors it will also show the temperature. Then you can easily compare what happens with and without silent mode and report back.

Personally I wouldn't be too worried about the temperatures unless they are either causing CPU throttling (I think it automatically cuts in at 95C) or making the outside of the chassis uncomfortably hot. CPU temperatures of 60 to 70C are definitely harmless unless there is external heating. It was frequent temperature variations that killed the Nvidia GPUs a few years back.

John

 

Haha, I'm a Dell XPS M1330 owner so I guess that's what I'm afraid of. Again, John, you come through with the goods.

Thanks very much,

Matt

 

Downclocks the cpu to 800Mhz if I recall correctly.

 

But what is there to be afraid of? Your first post indicates that silent mode is not degrading performance for your normal usage pattern. I don't Samsung installed an alternative device to get rid of heat such as by spraying liquid nitrogen onto the CPU.

John

 

Actually, a follow up to this if anybody's still reading - the fan thresholds on the Series 9 seem to be very sensitive when not in Silent Mode, and the performance is actually noticably compromised within Silent Mode.

When I wrote the initial post I didnt have much time to get acquainted with the laptop, but now I see when Silent Mode is enabled scrolling in documents is a lot choppier, browser tabs open with noticable hesitation (sometimes delays of up to 10 seconds) and videos play choppy.

After investigating with HWiNFO, it seems that the main effect of Silent Mode, other than raising the fan thresholds by large steps (they still come on after a long video) is downclocking the CPU to 798mhz maximum, which I think is causing the degraded performance.

Anyway, that's a long-winded way of saying, is there any way I can engineer a compromise? With Silent Mode on the computer is gimped and quiet, with it off it's fast and the fan is annoyingly on almost constantly, and it doesn't take much to get it spinning very loudly.

The two fan options in BIOS - auto and low - don't seem to change things too much. Is there any way I can:

a) Set my own fan temperature thresholds or
b) Set my own CPU clock speeds in Silent Mode?

I've searched for both but can't come up with anything

 

I wonder if Throttlestop would allow you to raise the CPU speed while in Silent Mode? I don't know of any utility to over-ride Samsung's fan speed settings.

John

 

When the fan is on during normal usage patterns, how does it compare to other laptops? Damm, I'm not liking this at all. Fan noise is a major issue for me...

 

I'm coming from a Macbook Air, which was silent unless watching Flash/HD video unless you put your ear to the grille, and the Series 9 is a lot louder.

I'm just sitting here web browsing with two tabs open with an ambient temperature of around 19 degrees celcius and the fan is a constant, audible whine, no matter what I can do in the BIOS.

The noise is mostly coming from the top grille, near the screen hinge, and I don't think my computer is defective in any way. I just think the fan is more audible on this than the Macbook Air, as that runs constantly but remains unheard.

You can of course turn the fan off with "Silent Mode", but that limits the CPU to 800mhz, which is not really what these powerful-lightweight ultrabooks are supposed to be about, and I can't find a program to tweak fan thresholds etc.

 

Arrrgggg... This is frustrating... I was really hoping fan noise was a lot better with this machine considering the price. I wonder how much research is going into noise reduction for laptops? So in silent mode, can your really do nothing? What about streaming movies FROM your laptop? Or torrenting something?

 

Unfortunately it's basic physics: If the CPU is working then there's heat to be dissipated and no one has yet made a flexible heat pipe which could pass the heat up into the display (which could make a nice passive radiator). It's impressive engineering to fit any fan into one of these thin chassis and it's no surprise to me that it's not very good at shifting air (if you want to hear a noisy fan, come round and listen to my Toshiba R500 when under load). However, I can offer three relevant points: (i) Ivy Bridge is claimed to be more power efficient so the fairly imminent Ivy Bridge S9s should generate less heat for the same amount of work and (ii) the 15" version (which I believe you are more interested in) has a slightly thicker chassis which would provide space for a bigger fan; and (iii) the majority of the S9 users find the fan noise quite acceptable.

John

 

Yeah, it may well be that I'm extra sensitive to it because I'm coming from such a quiet laptop. I still prefer the Series 9 to the Macbook Air, but this is the only place where it falls down in regards to its competition.

Anyway, the good news - using Throttlestop (version 3, but for some reason version 4 doesn't work) you are actually able to control the CPU clock speeds and mulitplier in Silent Mode, so it keeps Samsung's higher fan thresholds and you get a bit of extra speed. It's not ideal - the fan kicks in at 59 or so c and stays on for a good long while - but it at least gives you a measure of control

Thanks again John for your advice,

mjm

 

I have no audible noise from my fans even when under heavy load. When just web browsing, and typing office documents, my fans don't even spool up. Its dead silent and still runs cool. I'm very impressed.

 

either we have different sensitivities to the noise (likely, because I'm pretty anal about it) or mine is defective (possible, but seeing as i bought it overseas I'm not really willing to send it back for a few months to be told it's fine)

 

mjmcss, I've never heard my fans either.... but I haven't seen 59 degrees. 52-53 at most so far.

 

Thanks. That's useful to know as a compromise. At what temperatures does the fan come on when not in Silent mode?

Regarding perception of fan noise, a lot depends on the ambient conditions. When I'm at home in a quiet room I notice fan noise a lt more than when I'm away. Also, Samsung may be using more than one source for the fans. The first batch of the NP900X3B to be released in UK seemed to have a fan problem.

John

 

Currently in a loud room at work on the 900X3A-B06US and the fans are on low at 46 C. Not audible unless you put your head up to the keyboard, but as I say it's a loud room.

I've got a suspicion that Silent Mode does more than raise fan thresholds and downclock the CPU, as in Silent Mode with the CPU free to go all the way up to 1.6ghz and a 14 multiplier performance still seems slightly lesser. I'm not a benchmark guy, I'm just referring to general use (internet/document creation/video playback).

My suspicion is Silent Mode also changes memory usage and graphics settings, but I'll check on HWiNFO tonight. I'm surprised there's no community-created application for fan speeds though, but Throttlestop does a good job of managing the CPU at least