UPDATE 15.3.2013: Today 10.8.3 update came out and it seems to work smoother. Still, applying these tips will give you even smoother performance.
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So, you have noticed that Mountain Lion (10.8.2) on your new or old Mac feels sluggish and now you are reading this. Good. In this article I’ll give a few extra tips on how to improve this. Keep in mind that these are merely ADDITIONAL tips that do work, and you shouldn’t ignore and apply the more general tips explained elsewhere (make sure you have enough RAM, upgrade to SSD, have enough disk space left). Let me point out that Mountain Lion DOES invariably feel laggy also on relatively new and capable machines such as:

MacBook Pro quad i7 late 2011
(2.2GHz quad i7, 8 GB RAM, Radeon 6750M graphics and Intel HD 3000 graphics, 128 GB SATA3 SSD)

MacBook Air dual i5 mid 2011
(1.7GHz dual i5, 4 GB RAM, Intel HD 3000 graphics, 128 GB SATA3 SSD)

With these tips I substantially improved performance on both of them. These methods will also work and improve performance on older Core 2 Duo Macs as well, but I cannot tell whether the results will be as great. One thing to add: the explained methods work very well and Mountain Lion will work faster to the point of feeling very fast, yes, yet still not as fast as Snow Leopard 10.6.8 – at least on my quad MBP. That’s why I currently prefer using Snow Leopard 10.6.8 to Mountain Lion 10.8.2, which is something I wrote about in my earlier post. » Read more: Speed up Mountain Lion

At the time of writing this post, the latest version of OS X is 10.8.2 Mountain Lion. While it brought many nice features and definitely is nicer and faster than Lion, it also comes with some compromises. I already wrote about how Apple uses power throttling in order to make battery run longer and this behavior persists in Mountain Lion. » Read more: Downgrade to Snow Leopard for performance boost on a late 2011 quad Macbook Pro

Are you running a dual boot configuration (OSX and Windows 7), presumably not on a very large SSD drive, and are often running out of space on a Windows 7 bootcamp partition? Instead of resizing the partition, there is a more simple solution – move some of the files from bootcamp partition to another partition/drive and provide a symbolic link to them.

If you use your Windows 7 bootcamp installation for gaming, then you probably ran into low disk space issue more than once, had to delete/uninstall games in order to install another one or temporarily move game files to another drive only to copy them back later. Fortunately, ever since symbolic links have been introduced into Windows 7, you can leave game files or directories elsewhere and simply provide a symbolic link to them. Have in mind that this will work only with Windows 7 installed, not with Windows XP (which doesn’t have symbolic linking). » Read more: Extend space of a Bootcamp partition with symbolic links (Win7)

Update 4.5.2013: The methods I originally described in this post did work fine, but I just wasn’t completely satisfied with the image quality (still jaggies here and there even at 2xMSAA and general lack of detail at 0xMSAA). Turns out the only real fix for my eyes is to use 4xMSAA with postAA low, no injector, no sharpening, no color fixes (other settings: textures+shadows low, effects+mesh: ultra, terrain medium, deco high, no AO). I was surprised to find that 4xMSAA actually does work smoothly on my 6750M with measly 512 MB VRAM at 1366×768 (non-native though, but also non-scaled of course) resolution with new 13.5 catalyst beta drivers. Had to free as much VRAM as possible (desktop at 16bit color in non-aero mode, using only some 5 MB VRAM, kill hardware acceleration in Firefox) and remove all injectors though (FXAA/SMAA/SweetFX) because they were hurting performance in combination with 4xMSAA. The game now looks sharp and smooth, is a pleasure to watch and play, graphics are easier on the eyes and spotting enemies is much easier with details so carved out and image so clear. So basically if you can afford 4xMSAA at a decent (laptop) resolution even at some low settings, go with it.

Other honorable mentions: The other method I tried prior to settling for 4xMSAA was to use SweetFX injector (a great injector btw) combo with SMAA, sharpening, color vibrance and contrast correction, ingame PostAA low and 2xMSAA. Looked pretty much great, especially the colours, you might want to try that out if 4xmsaa is not an option. In my “quest” for the perfect image quality I even came across a very interesting SSAA injector (download SSAA-Tool at http://www.tommti-systems.de/start.html). What SSAA (true supersampling which can actually be forced upon BF3) injector did in my case was to render the image at double pixels (2880×1800) and then display it downsampled to display’s native 1440×900 resolution. As you can imagine, the image quality is perfect this way, but it murdered my framerates in BF3 therefore it wasn’t even remotely usable, but with a high-end card (or a less demanding game) that would be a different story.

So the takeaway of this whole bf3 image improving oddyssey would be: some games can look near perfect with merely an FXAA injector (BC2 and countless others), but shader based antialiasing (FXAA or SMAA) alone is not enough for BF3, this game is simply made the way it is made, the injector spells work only partially. Use 4xMSAA with BF3 (or at least 2xMSAA). At least for me, 4xMSAA on low has better image fidelity than 0xMSAA on ultra, the difference between jaw-dropping versus sort-of-ok-but-kinda-sloppy. Happy gaming, over and out.

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The original post 14.5.2012:
This is a follow-up post to the previous one. This time around, we’re going to sharpen BF3 graphics further and improve the image quality in BF3, at no performance cost and start enjoying some high-fidelity visuals. No, it’s not yet another post about DANOC FXAA. » Read more: Alternative way to get sharper, crisper graphics in Battlefield 3

The takeaway first: Battlefield 3 (multiplayer as well as campaign) is very playable on 9600M GT with 256MB video RAM and a mid-2009 dual core Macbook Pro, with a few tweaks applied and a few compromises, mostly the resolution at which the game can be played comfortably. » Read more: Battlefield 3 playable on Nvidia 9600M GT and dual-core Macbook Pro

To avoid a lengthy intro, here is the thing: at some point OSX – and I’m talking specifically Snow Leopard 10.6.8 here – started feeling sluggish. The transitions didn’t feel smooth anymore and the general feeling was that OS was not as snappy as it used to be. Turns out all this has something to do with OSX’s built-in GPU power management, which reduces GPU clock speeds in order to save power. So what we want to do here is to turn this sort of throttling off and keep the GPU at its maximum speed at all times. » Read more: Get rid of OSX lag and run your Macbook Pro GPU at full speed