Is it possible to turn of hyperthreading on my PCS laptop?

[Fuzzball]

Got a laptop from PC Specialist a year and a half ago. Here are the specs:

Chassis & Display Vortex Series: 17.3" Matte Full HD LED Widescreen (1920x1080)
Processor (CPU) Intel® Core™i7 Quad Core Mobile Processor i7-3630QM (2.40GHz) 6MB
Memory (RAM) 8GB SAMSUNG 1600MHz SODIMM DDR3 MEMORY (2 x 4GB)
Graphics Card NVIDIA® GeForce® GTX 675MX - 4.0GB DDR5 Video RAM - DirectX® 11
2nd Graphics Card NONE
Memory - Hard Disk 120GB INTEL® 520 SERIES SSD, SATA 6 Gb/s (upto 550MB/sR | 520MB/sW)
2nd Hard Disk 750GB WD SCORPIO BLACK WD7500BPKT, SATA 3 Gb/s, 16MB CACHE (7200 rpm)
RAID NONE
mSATA SSD Drive NONE
DVD/BLU-RAY Drive 4x BLURAY ROM, 8x DVD ±R/±RW & CYBERLINK SOFTWARE
Memory Card Reader Internal 9 in 1 Card Reader (MMC/RSMMC/SD: Mini, XC & HC/MS: Pro & Duo)
Thermal Paste ARCTIC MX-4 EXTREME THERMAL CONDUCTIVITY COMPOUND (£9)
Sound Card Intel 5.1 Channel High Definition Audio + SPDIF/MIC/Headphone Jack
Bluetooth & Wireless GIGABIT LAN & WIRELESS INTEL® ADVANCED-N 6235 (300Mbps) + BLUETOOTH
USB Options 3 x USB 3.0 PORTS + 1 x USB 2.0 PORT AS STANDARD
Firewire 1 X 1394a FIREWIRE PORT
Battery Vortex Series 8 Cell Lithium Ion Battery (5,200 mAh/76.96WH)
Power Lead & Adaptor 1 x UK Power Lead & 220W AC Adaptor
Keyboard Language INTEGRATED BACKLIT UK KEYBOARD WITH NUMBER PAD
Operating System Genuine Windows 7 Home Premium 64 Bit w/SP1 - inc DVD & Licence (£79)


I use it mostly for gaming and I'm currently trying to push a little bit more out of it. I've heard that turning off hyperthreading in the BIOS can increase gaming performance as it allows the CPU cores to focus on the one task of running the game.

I tried looking in the BIOS but couldn't find an option to disable hyperthreading. I read from someone on another Internet forum that most modern laptops don't have the option to turn it off. Is this the same for PCS laptops? Or is there some secret tweak I can perform hidden away somewhere?

 

[mrducking]

first of all, thats the weirdest thing i have heard in a while, and let me explain: if you are not multitasking there is no need for the cpu to use hyperthreading, just play with everything else closed and you should be at your max potential, BUT i may be wrong, so correct me if so, please

second, unless im wrong it is pretty weird for laptops BIOS to have a lot of things enabled, but hyperthreading sounds like the kind of thing you dont want people messing with, so yeah, there is probably not an option for it

lets hope someone else answers too, you picked my interest with this

 

[SpyderTracks]

As mrducking says, the laptop BIOS is pretty restrictive and cpu controls aren't present. Are you having performance issues or just trying to max it out a bit further?

 

[ubuysa]

I agree with all the above regarding the likely impossibility of turning hyperthreading off.

But I think you're clutching at very slender straws here. Hyperthreading, like real multitasking, only shares CPU resources between two processes when the process in control has stalled - ie. it can no longer execute (because it's waiting for an I/O or for another process to complete or for you to press a key, for example). Hyperthreading is not a time-sharing system where a running process looses control even though it wants to keep executing, it's mainly event driven. That's why hyperthreading benefits some applications more than others, those that voluntarily give up CPU control benefit more than those that don't.

So I think any benefit to your one game that you might potentially see is likely to be infinitesimally small, especially if the game is itself multi-threaded as I expect it will be. In any case, it's a fallacy to imagine that because you're just playing one game that there is only one process executing, the OS is also running a great many processes at the same time, and good OS performance is critical to good application performance.

I don't know whether your game ever does I/O to the disk, but if it does that will be where your best performance benefit will be found. Moving everything related to the game to your SSD will make a huge difference if it does do I/O. It will also be worth ensuring that everything related to your OS's I/O is on the SSD too, if the OS ever has to do an I/O to the HDD in support of your game you'll get a performance hit.

 

[mrducking]

as ubuysa said, you have two options to better your performance:

-upgrade your hardware

-OverClocking, be it for the gpu or the cpu

the other option is to lower or disable some things, like AA

unfortunately, reached a point you have to buy upgrades or lower image quality, no way around it

and please, if you find it, dont play with hyperthreading, bad things happen when you touch things like that, i have done it with others things and got me some expensive paperweights

 

[Fuzzball]

Alright, I get the message. I can't disable hyperthreading on my laptop and it's probably not a good idea to do so anyway. Anyway improvement would be tiny.

I was just wondering because I'm playing a fair bit of the Total War games at the moment (ROME II and Shogun 2) and performance on the games' campaign maps is a bit spotty. It's not terrible, just not as smooth as I'd hoped it would be, considering my hardware is above the recommended specs and performance in battles is fine. Lowering the graphical settings in-game has no effect. I guess in the end my hardware is perhaps just not good enough to run the campaign maps super smoothly. I think it might be my CPU that's the weak link, as when I look at the Task Manager when playing the games, it shows a huge amount of activity in one core and little in the others. So I guess the games are only using one core, and so only 2.4Ghz of power.

As for what ubuysa said, there are a couple of terms I don't understand...
-What is "multi-threading" in comparison to hyperthreading? Is that where a program/game uses more than one CPU core?
-What is "I/O"?

I obviously have my OS on the SSD, but it would be interesting to see if putting the Total War games onto my SSD would improve their performance. Unfortunately, I only have enough space left to maybe fit one of them.

 

[mrducking]

some total war games are known to be really ineficient in the campaign map, so im pretty sure, having played all except shogun 1 and 2, that is the game or HDD rather than the rest, it may also be that the game is using the integrated graphic instead of the gtx 675m, so check it out just in case

now, I/O means input/output, meaning anything that requires interaction with other things (mouse, keyboard,... whatever)
multithreading is when you have more than one logic or computing thread, and this i hope someone can explain, because i know what it is and how it works, but have no idea how to explain it

 

[ubuysa]

<snip>

-What is "multi-threading" in comparison to hyperthreading? Is that where a program/game uses more than one CPU core?

Multi-threading is an application design issue. Instead of coding an application as one single process (or thread) more efficiency can be obtained by coding the program as multiple processes, each process can run concurrently on multiple CPUs. Obviously the design of a multi-threaded application is much more complex because the processes have to have a reliable communication mechanism and you can't guarantee that any two processes will be executing at exactly the same time. Multi-threading is designed to take advantage of multiple CPU architectures such as we have today (multi core architectures as you say). It's pointless if your PC has only a single CPU engine.

Hyperthreading is an Intel technique whereby a single CPU engine appears to be two. This is achieved by creating two instances of all the queues and execution status flags etc., one per process, but these two 'logical CPUs' share one physical (or real) CPU. So only one process at a time is actually executing instructions, the other is waiting. When an event occurs that causes the executing process to be non-executable (because it's waiting for some external event - like an I/O) the other process will be given control of the physical CPU, until it also has to wait for an external event.

Hyperthreading also explains why Windows sees twice as many CPUs as you actually have. My Intel i7 for example, contains four physical CPUs or cores, so four processes can be executing at the same time (this is called multi-processing). But because hyperthreading creates two logical CPUs per physical CPU Windows reports that I have eight CPUs installed and it (Windows) will multi-task up to eight processes at the same time on each of those eight (logical) CPUs.

Hyperthreading is very similar to mulit-tasking. This is where many processes appear to be executing on the same CPU (or logical CPU) at the same time. Multi-tasking also relies on the fact that all processes execute for a time and then stall, waiting for some external event. When this happens the OS begins executing another process on that CPU. This is why when you look at your Task Manager for example, you'll see dozens of processes running simultaneously, even though you may only have a diadic (two-CPU) or quadratic (four-CPU) processor chip. All those processes "think" they're running at the same time but in fact the OS is giving them to the CPU only for short periods.

I hope that makes some sense?

-What is "I/O"?

Input - Ouptput. It's when the CPU needs to read data from outside the CPU/RAM (from SSD or HDD or a USB device, or even the keyboard and mouse, etc.) or write data out to an external device (SSD, HDD, Screen, Printer etc.). Because an external device is involved I/O takes a long time relative to the CPU cycle time, so any process doing I/O cannot execute on any CPU - because it has nothing it can do until the I/O completes.

I/O to spinning metal hard disks is painfully slow. A good I/O to a hard disk will take around 10mS, but in those 10mS most modern CPUs can potentially execute millions of instructions. So a process doing an I/O to a hard disk is voluntarily giving up the chance to execute millions of instructions whilst it waits for the I/O to complete (and multi-tasking and hyperthreading will switch the CPU away from that process and give the CPU to a process that can execute). This is where a multi-threaded application wins out. In a single threaded application the whole application stops when an I/O is done, but in a multi-threaded application only the process doing the I/O stops, the other processes in the application can continue executing.

I obviously have my OS on the SSD, but it would be interesting to see if putting the Total War games onto my SSD would improve their performance. Unfortunately, I only have enough space left to maybe fit one of them.

Yes it would be interesting. I don't know whether your game does disk I/O but if it does putting the game on the SSD will make a HUGE difference to performance.

 

[Fuzzball]

Well after finding it impossible to simply move the files over to my C: drive and have Steam access them, I re-downloaded all of Total War: ROME II onto my SSD C: and now the game seems to run a fair bit smoother on the campaign map. I guess having things on an SSD really does make a difference. Next computer I get I'll make sure the SSD is bigger so I can fit more games on it!

 

[ubuysa]

Well after finding it impossible to simply move the files over to my C: drive and have Steam access them, I re-downloaded all of Total War: ROME II onto my SSD C: and now the game seems to run a fair bit smoother on the campaign map. I guess having things on an SSD really does make a difference. Next computer I get I'll make sure the SSD is bigger so I can fit more games on it!

I've spent most of my adult life working in large mainframe system support. Although the OS's and chip technology is different in the PC world all the basic principles remain the same. The very worst thing any program can do is an I/O to a hard disk drive, this is because it takes so long. That's why SSD, which operates at the bus speed, is so much faster.

To give you a feel, and this is only a very rough comparison, if you imagine that a modern CPU can execute 1 instruction per clock cycle (it's typically not that fast, most instructions take several clock cycles to execute) then a 2.4GHz CPU is executing very roughly 2.4 billion instructions a second. As I mentioned before, a good I/O to a hard disk takes about 10mS. Now, if we slow down the CPU so that it's executing 1 instruction per second how long do you think an I/O to a hard disk takes on that timescale? Well on this scale it takes over 9 months! Just look at all those instrcutions you could have been executing had your I/O been faster or not done at all......

That's why hard disk performance is absolutely critical to overall computer performance and why if your PC is running slow the first place you should look is at the hard disk. That's where the biggest improvements are to be had.

 

[mrducking]

I've spent most of my adult life working in large mainframe system support. Although the OS's and chip technology is different in the PC world all the basic principles remain the same. The very worst thing any program can do is an I/O to a hard disk drive, this is because it takes so long. That's why SSD, which operates at the bus speed, is so much faster.

To give you a feel, and this is only a very rough comparison, if you imagine that a modern CPU can execute 1 instruction per clock cycle (it's typically not that fast, most instructions take several clock cycles to execute) then a 2.4GHz CPU is executing very roughly 2.4 billion instructions a second. As I mentioned before, a good I/O to a hard disk takes about 10mS. Now, if we slow down the CPU so that it's executing 1 instruction per second how long do you think an I/O to a hard disk takes on that timescale? Well on this scale it takes over 9 months! Just look at all those instrcutions you could have been executing had your I/O been faster or not done at all......

That's why hard disk performance is absolutely critical to overall computer performance and why if your PC is running slow the first place you should look is at the hard disk. That's where the biggest improvements are to be had.

aanndd thats why games nowadays require so much RAM, so you dont have to execute I/O

 

[Fuzzball]

And now I'm having to redownload the game again onto my HDD D:. Because Steam is so inefficient with its downloads. It wanted to update Total War: ROME II on C: today, but whenever Steam updates the game, it creates a whole copy of all the files in a "downloading folder". My C: drive didn't have enough space to contain two copies of the game, so I had to remove it from that drive. And for some reason this time when installing it on D:, Steam wouldn't recognise I'd already copied the files over, so now it wants to download over 13GB again. Gah! Just wanted to rant.