Update - 2/2/2010 by Datth

Manually adjusting this file is no longer needed as of 3.3.2 unless you're trying to run the game on specific cores. It is now uncapped so it will run on whatever core your OS deems as fit.

Players who would like to restore the old behavior can do so by updating the Config.WTF file by adding: SET processAffinityMask "3".


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I had no idea this thread would still be generating interest 2 years after I started it! I've edited out the old 4-core chart since Datth's chart is more useful anyway. I'm still happily using all my cores here. :)

In machines with more than 2 logical processors (whether they are multiple physical processors, multiple DualCore or single QuadCore processors, or DualCore + HT processors), a new variable is saved to the config.wtf file.

The processAffinityMask variable is a decimal number composed of a binary mask representing which cores WoW will allow certain threads to be scheduled on. By default, this variable is set to "3" representing logical processors 1 and 2.

The chart can be extended to this format:

╔════════╤════════╤════════╤════════╤══════��═╤════════╤════════╤═══���════╗
║ Core 8 │ Core 7 │ Core 6 │ Core 5 │ Core 4 │ Core 3 │ Core 2 │ Core 1 ║
╠════════╪════════╪════════╪════════╪════════��════════╪════════╪═════���══╣
║ +128 │ +64 │ +32 │ +16 │ +8 │ +4 │ +2 │ +1 ║
╚════════╧════════╧════════╧════════╧════════��════════╧════════╧═════���══╝

On my system, I seem to get better performance (higher FPS) when changing the mask to "15", even though I only have 1 physical processor with 2 cores and HyperThreading. I'm curious to know, which threads does this mask schedule?

With the default affinity mask set to cores 1 and 2, I actually get poorer performance than when I disable HyperThreading. But enabling HyperThreading (to get those extra two logical processors) and changing the mask to "15" seems to give me about 20 more FPS.

Are there any consequences to changing this setting, such as instability? Are there any recommendations for changing it from its default value to achieve better performance on systems with 4 or more logical processors?

You can use this to let WoW run on a specific core(s) but it only works up to two cores. If you set it on 15, you just let the game use 2 out of your 4 processors but you didn't tell it which ones.

As far as I know, it's set to default at 2 (first two cores). Your chart above describes how the number (when translated to binary positions) describe what you can set it to to enable the cores you want. I think on a hyperthread system, the system counts [Real core][HT core][Real core][HT core]. You might want to try "5" instead of "15"

Also note that some system drivers take advantage of both Hyperthreading and multicore so you might notice a bigger bump in certain hardware/driver setups.

It's technically not backwards as the OP started 1 from the left column. In your column, you started one on the right, binary style. It's just your chart inverted, making it a bit non-computer friendly. :)
I have a hard time noticing it until you mentioned it. I can invert and flip things in my head at will so I can read things spelled backwards, upside down or inverted.

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Q u o t e:
I have this on another thread, but since I posted it, I found your thread.
Is this thread dead?
Here was my question:
I have a AMD Quad Core processor. AMD Phenom 9600 Quad-Core processor 2.30 GHz. I saw some where posted that you can modify the Config.WTF file, so as to make WoW run on more than 1 processor. Is this true? If so, how do I do that?

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It natively does that by itself unless you restrict it via Task Manager or the processAffinityMask cvar.

Yeah. Leave it alone unless you have some specific needs, like you're running a vent server or something on its own core and you don't want anything else to touch it.

Just an update, this cvar can support up to 32 processors. Just extend the binary to fit your needs.

There is no three cores, but you can use whatever setting you want. Just beware of the HT cores and not try to load the game into only HT cores.

The game only allows binary conversion of the numbers you want. Basically add the numbers:
i7:

|X |X |X |X |X|X|X|X|
+--+--+--+--+-+-+-+-+
128 64 32 16 8 4 2 1

Performance will vary from system to system. You'll have to experiment yourself.

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Q u o t e:




Confirmed. I set my AMD quadcore 9850 from affinity 3 which is default to affinity 10 and my fps nearly doubled in Dalaran. I went from about 18fps to about 32fps. Please do something about this blues. It really needs to be addressed. I really don't want to have to hack wow to get it to perform better.

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System setups are too different for us to start setting "optimal" affinity settings. If your system likes the 2nd and 4th cores being used, you're free to do that. You're also free to have multiple copies of World of Warcraft using different processaffinitymask variables for multiboxing if you're into that kind of stuff. We default on 2 cores (processaffinitymask 3).

Experimenting is the way to go, or you can go with what other people use. At least you don't have an i7 and have up to 255 values to play with. :)

7 is the max that you can use for a triple core. 15 for a quad core, 31 for 6 cores, 255 for an 8 cores.

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Q u o t e:


It DEFAULTS to 2 cores.

However 3.1 made it so everything runs off 3 separate threads instead of the previous 2. IF you play with your affinity settings, you can move 1 of the threads to a 3rd core.

Its not technically tri/quad support as wow doesnt do it itself, but you can FORCE it to.

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There's actually a ton of threads. The optimization works for 2 cores but that doesn't stop you from telling Windows that it can send threads to different/more cores using processaffinitymask.

If you have an i7, remember that there's a little turbo feature that you could take advantage of.
http://www.intel.com/technology/turboboost/index.htm
Something to keep in mind for people trying to tweak processaffinitymask.

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Q u o t e:
So, for only a dual core, there is no need to implement this? My config file doesn't make mention of that variable. I'm assuming there is no need. Correct?

My cpu is amd 4400+ dual core.

TY.

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Dual core machines should default to 3 (first and second).

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Q u o t e:


Can you explain this further please? Are you saying the default detected for dual core systems should be 3? If so, and it isn't, should we change it to 3? I guess other than copy pasting the variable given, I'm not sure what to do next, still.

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If you have more than 1 core or physical processor (think a minimum of an Athlon MP system with 2 processors), processAffinityMask is automatically set to 3. It's the decimal value for 1,1
You don't need to change it unless you want it to use a specific core. If you want it to use the first, change it to 1. If you want it to use the second, change it to 2. If you want it to use both, use 3 or leave it alone since it's already the default.

The OP's chart is inverted. I'm going to update it to this type of format:

╔════════╤════════╤════════╤════════╤══════��═╤════════╤════════╤═══���════╗
║ Core 8 │ Core 7 │ Core 6 │ Core 5 │ Core 4 │ Core 3 │ Core 2 │ Core 1 ║
╠════════╪════════╪════════╪════════╪════════��════════╪════════╪═════���══╣
║ +128 │ +64 │ +32 │ +16 │ +8 │ +4 │ +2 │ +1 ║
╚════════╧════════╧════════╧════════╧════════��════════╧════════╧═════���══╝

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Q u o t e:
I have a feeling I know why the dramatic increase in performance on i7 systems going from 3 to 255 (or anything higher, really). Setting 3 implies it runs on the first two cores - in this case physical core #1 and virtual core #1 - so WoW is really running on a single physical core. Setting the affinity to anything higher forces it onto two (or more) physical cores and performance jumps appreciably as a result.

These guys are right - WoW needs to autodetect the number of cores and set the affinity correctly. Or you need to post better instructions about this issue so people can get the performance out of a high end system they've built.

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3 has something nice going along for it too: Intel Turbo Boost. Some systems run faster with that than a different affinity setting.

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Q u o t e:
I personally have a OCed I7 920 running at 3.8ghz and run processAffinityMask to 85 as it used only my physical cores. I honestly don't think WoW can process using HT cores as when I set to 255 it lowers my FPS by 10.

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HT helps on smaller scales. Pentium 4 with HT on tends to run World of Warcraft a lot better than equivalently clocked P4s without HT. On a larger scale like the i7, anything goes.

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Q u o t e:


Will WoW ever use all 4 cores? I'm thinking about getting a comp with AMD Phenom II Quad-core 2.8GHz. Its a nice processor and I dont want it to go to waste.

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You can use this variable to let Windows distribute threads to your other cores. They won't be doing very much work overall but may give you a slight boost.

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Q u o t e:


So if I am understanding correctly, WoW still only uses two cores, while Windows will, instead of using the same two 'default' cores, be split into other, unused, cores?

Core 1-----Core 2------Core 3------Core 4
WoW--------WoW---------Windows etc.

I dont know much about this whole thing but bottom line, when will WoW itself use four-cores?

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World of Warcraft is capped to two cores because we set the default processaffinitymask to 2. There's actually quite a few threads that the game runs but mainly 2 or 3 decent-sized ones and a dozen little ones. Windows can distribute all of these among other cores if you tell it to but you can't specifically tell what thread will go where. You may want to look up the purpose of affinity masks and what it can do for you. http://en.wikipedia.org/wiki/Affinity_mask

Addons are managed by the game. You can't set aside a core to run a specific part of WoW.

There are stuff in that mod that can push the game to use too much memory and crash. Beware when you use such a thing.

This thread isn't for the weak-of-heart or has questions about what affinity does. Those questions will be deleted from this post.

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Q u o t e:


Is the crash due to a client side limitation of usable memory or is it based on a system crash due to the mod wanting to use more than is available in the system?

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WoW is a 32-bit program. It only has access to 2 GB of memory. Once you go over that, you get a wall-of-text crash.

Just tossing something into the mix: i5 turbo mode behaviors - http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=3634&p=5

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Q u o t e:


Indeed. I'm hoping to see this fixed up, as in all honesty, it wouldn't be too difficult to do. Like I said, this is the ONLY application that I've seen that shows this kind of behavior, and it's definitely hindering performance for a good amount of users - especially people that would be on something such as a hyperthreaded dual core.

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There's only three sets of chips to break this rule - the high-end Pentium D Extreme processor, higher-end model i5s and all i7s. If you want to see it done differently, you'll want to post on the Suggestions forum.

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Q u o t e:


Posted. :)

http://forums.worldofwarcraft.com/thread.html?topicId=19820632868&sid=1

I don't know how much this will be able to do in regards to seeing this changed, but it would be a good thing to see. Since Windows will always use a processor to its maximum potential by spreading the load out, this could also increase general system performance when alt-tabbed out of the game.

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Then you have new chips like the i5s messing up the entire picture, where a clock speed bump will net greater increases for the game than spreading it out ;)

This isn't the thread to get FPS help. It's more about this variable than anything else. The first generation Phenoms do not perform very well so you're not really going to get much of a push there since this game is more CPU-oriented. You should try checking out the new Athlon II X4s that were released today. They're faster than your first gen Phenom and their price is really low.

There shouldn't be any problems with that.

I've built a budget Athlon II X2 250 system about 2 months back, with 4 GB of RAM and a 4850 512 MB card. It was crusing around 50+ in Northrend just flying around and doing quests on High settings. I took it to Naxx 25 and didn't see any numbers below 30. A GeForce 9800 should get equivalent FPS. An Athlon II x4 should be better after the processAffinityMask change. Your best bet is to make a new thread and explain your issue in detail, and also check the report in the NVIDIA Control Panel -> System Information and make sure you're getting the full PCI Express 16 lanes.

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Q u o t e:
Hey guys,

I've got a single CPU, duel core with Hyperthreading enabled under BIOS.

My config file says Cores Detected = 2

shouldnt it read 4 with hyperthreading enabled? I tried manually setting it to 4 and adding the Affinity mask line since that was also missing and when I next loaded Wow it rewrote the config file to set the cores back to 2 and the affinitymask to 0.


Any ideas??

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The only dual core processor with Hyperthreading is the Pentium D Extreme Edition. These chips are really rare and costs a bit over $1k at the time for that part alone. Is that what you have? If you put in invalid values, it's going to kick out your numbers and use the defaults.

Pentium 4s only come with one real core. Some of the later models come with Hyperthreading so systems tend to treat those as dual core parts. There's a lot of articles online dealing with the Pentium 4's HT capabilities so try searching for it.

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Q u o t e:
Anybody know why if I set processAffinityMask to 255, save, then start wow. Upon quiting WOW and looking at the cfg file, its set to 0? Additionally, if I go into wow again, then close, the processAffinityMask line is gone alltogether from the .cfg file? Cant find it with a notepad search.

Seems to not do this when I set it to 15 though.

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Phenom X4 is a quad core processor. 15 is its max value (8 + 4 + 2 + 1). You can't turn on cores that don't exist (128 + 64 + 32 + 16 + 8 + 4 + 2 +1). You set it to a goofy setting and the game will reject it.

Yes

Windows is usually smart about thread management so it wouldn't hurt the system much. Full screen mode tends to beat windowed mode or windowed+maximized mode but if you're not doing much to tax your desktop composition engine, WoW should still run well in windowed mode.

Which variable works better for you will be specific to your setup. It's one of those try-it-and-report-results type of thread. The default is 3 but you can always remove the entire SET processAffinityMask line if it's giving you trouble or unexpected results so it's not like it's going to kill your system.

E6750 is a dual core processor so think of how to enable both cores in binary. That will give you your max value.

Hint: WoW defaults on the max value for a dual core processor.

Check the first chart. Start with 0, then look at which cores you want on. First position, you add 1. Second position, you want to add a 2 on top of it. You only have those two so it's 1+2 = 3 :)

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Q u o t e:
...........................pls help read my message

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I don't see any messages from you. If you mean what's in your signature, you need to call Billing. Hijacking another thread again will get you a forum ban.

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Q u o t e:
Quick question, the processaffinitymask is the only value that needs to be changed, yes? And 240 means it'll be using the last four cores (5,6,7,8)? When I took a quick peek at the Task Managers Affinity it was set to those cores, which means the 1, 2, 3, and 4 will be free for WIndows 7 (64 bit) and other applications, aye?

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Yes. You'll effectively use the last two cores + two hyperthread cores.

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Q u o t e:
Core i5 is dual core with HT (4 logical)

bwaa-hahaha

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No it's not. It's 4 real cores with no HT. That's what differentiates the i5 720 from the i7 800 series: http://ark.intel.com/ProductCollection.aspx?familyID=42912
i7 800 and 900 series = http://ark.intel.com/ProductCollection.aspx?familyId=28037

I only know of the consumer side of products that are out, and a few rumors here and there. :)

I'm not sure about the deep inner workings of Win7. I do know that the game itself throws networking processes into other threads and Windows can do what it likes to those. I'm not sure where Windows TCP stuff runs at. It sounds like a question for the MSDN forums.

It's referenced to in the System Performance Guide sticky :)

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Q u o t e:


Process parking m'dear? Confused as to what you mean, but...no I haven't I don't think?

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It's something in Windows 7 that is causing rare performance problems. I don't notice it on my home i7 / Win7 system but some people are getting microstutters and odd behavior. _____User tips and tricks

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Q u o t e:




How do I type 15 instead of three, when i try to backspace on the number it wont let me. How do i unlock it.

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I'm not sure what you mean. Can you elaborate?

Try Microsoft Wordpad instead of using Office. Yes, the number is 15. Hopefully you don't have Windows Vista or 7, and decided to install the game in Program Files. That'll get it locked.

Just log onto the game and type this to your chat window:

/console processaffinitymask 15

Hit Enter. Exit the game and then log back in. That should do the same as what you're trying to do. For future reference, please do not clog up an old thread like this with unrelated issues. This thread is for advanced users. Learn UAC and what it locks on a Windows Vista and 7 system. This thread is about the variable itself, not how to put it in.

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Q u o t e:
As much of a help this has been, my curiosity has me wondering.

Wouldn't it be a fairly simple task to let us use a number that lets wow use all 8 "cores" of an i7?

Obviously relatively few wow players have an i7, but for those of us that do, why not?

The boost going from using 2 cores to 4 cores was massive, while I don't expect as large a boost, it may improve still, and I'd love for my favorite game to be able to use my system to its fullest.

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2 words: Turbo Mode. It won't kick on if WoW is using more than a certain # of cores. WoW gets more of a speed boost with Turbo Mode more than using more cores. Main game threads go up, everything else gets an easy ride.

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Q u o t e:
Running Win7 64-bit on an i7 920...

I tried changing the processAffinity var in config.wtf and wasn't seeing any fps changes, then tried the disable core parking trick which fixed the problems I was having. But with any affinity mask I used (3, 10, 15, 85, 128, 240, 255) performance remained the same and I was only using core 1 + 1 HT (and yes I quit out of wow after each change and reloaded the game). I tried changing the affinity setting manually in the task manager and went from smooth but mediocre fps to 35+ in the laggiest parts of Dalaran.

I finally figured out I had to run WoW in admin mode to get it to load the changes to config.wtf (affinity set to 255), and now it runs just as well as manually setting the process affinity. But for some reason when I go to the task manager to double check if it's now set to use all the cores while the game is running, I get an error saying "The operation could not be complete. Access is denied." So I'm wondering if I'm missing something since I'm the first person in this thread to mention having to run WoW as admin to get these changes. Am I doing something wrong? :(

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You're probably playing with the wrong set of configuration files. If your game is in Program Files or Program Files (x86), you're going to load the VirtualStore's copy of the config.wtf file when you run it normally. When you run it as an admin, you're going to load the local copy of the config.wtf file.

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Q u o t e:
I seemed to have lost my performance boost with the patch. I checked the file, thinking maybe the patch changed the number but it's still at 255. My performance though is back to pre edit levels. I'm very disappointed :(.

Any ideas? Running i7 here.

Might it have something to do with this:
http://forums.worldofwarcraft.com/thread.html?topicId=21730645881&postId=217284498685&sid=1#0

Started happening after the patch.

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My i7 is behaving the same way before and after patch 3.3.0.

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Q u o t e:
Hi Datth,

I'm very curious as I stumbled upon this thread trying to boost my performances in game. I'm not the most knowledgeable on these matters but I like to do a bit of research. :) Anyways, I'm curious because I own the now old Pentium D Extreme 965 model and I've been trying to find some specifications for setting the AffinityMask for it, But I'm not having any luck. From what I see in my Device manager that processor seems to act like 4 cores (to my understanding 2 of these being physical and the remaining 2 Virtual caused by the Hyper-threading?). I would like some advice as to what values I could test out to see if I get an increase in performance.

Running on XP with SLI setup of 2 X 7950 GX2 (so bassically 4 cards)

Any tips would be greatly appreciated. Thanks :)

Edit: Forgot to mention I am already using SET gxTextureCacheSize "512" as I can only base that command off one card. Correct me if I'm wrong because obviously I would like nothing more then boosting that up to 2048! LOL

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I think cores 0 and 2 are your real ones while 1 and 3 are your hyperthread. 5 (1 + 4) would be your numbers if you want to avoid the hyperthread cores.

It's generally not a good idea to set your gxTextureCacheSize to all of your video card's memory as you want some left over for stuff like buffers and other programs (especially Vista and 7).

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Q u o t e:
I'm upgrading my CPU.

Currently I have an AMD Phenom X3 8750 Black Edition Toliman 2.4GHz 3 x 512KB L2 Cache 2MB L3 Cache Socket AM2+ 95W. (overclocked to 3.0Ghz)

Upgrading to a AMD Phenom II X4 955 Black Edition Deneb 3.2GHz 4 x 512KB L2 Cache 6MB L3 Cache Socket AM3 125W (going to overclock to 3.8Ghz or maybe 4.0Ghz if it's stable enough)


My affinitymask is set to 7 right now but once I get the new CPU I'm setting it to 15.

I'll post if I get an improvement in FPS. Right now at 1920x1080 24-24-2, max settings except shadows which is turned to min... in Dalaran I get anywhere from 20-40 FPS. In 25mans during heavy spell casting I get 0-5 FPS.

I'm hoping this upgrade will at least fix my 25man raiding FPS because right now I can't really raid without causing at least one wipe per night.

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I built four Athlon II X2 machines: two 250s and two 240s. They're not showing any drops in 25-man content but their addons usage is pretty light (SCT/SCTD + Pitbull). What issues are you having? What video cards are on those? Addons and video cards with low fill rates will get hit the hardest on spells.

Going to a tri-core or quad core processor won't give you any improvements as the main section of the game is still on a large thread. The fill rate on the 9800 is more than enough except at very high resolutions for a 25-man raid. I'd suggest installing FuBar and SpamFU and see if other people are causing your framerate to plummet. It can view hidden channel stuff and addons that people spew out at you. Also check your NVIDIA Control Panel - System Information to see if your video card is on PCI Express 1x or 4x mode since yours is a 16x card.

I heard thru a g*%%@vine that the old default of 2 cores may be removed in a future patch. Those that will want to restore it can use the processaffinitymask value of 3.

Updated with new info.

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Q u o t e:
Hyperthreading is an Intel only technology, you dont have it.

The game usually handles dual core CPUs just fine, you dont need to mess with the affinity mask.

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For now. I'm interested in seeing AMD's implementation of it. I think it's in Bulldozer?