The new ATI Graphics Cards from the 7970 series are super-fast, while being single GPU systems (the upcoming 7990 will be a dual-GPU 6GB Graphics Card). Besides being quite "cheap" (around 500€ in Europe, $589 in the US, they are said to be supported in OSX soon (see also a discovery by netkas) - until then, there is a current way how to use them (although not accelerated) with chimera. Props go to Shrapnl from the tonymac86 forum:
I was able to force my 7970 into a higher res (still unaccelerated of course) via the org.chameleon.boot.plist with the following:
Of course, you can overclock the 7900 Series just fine. There are "Waterblocks" from Aquacomputer for the 7900 series, as outlined by Geeks3D.
Of course, the GPU runs quite fast without overclocking, still you could go faster. Below: Shamino has overclocked a Radeon HD 7970 under LN2 with the following clock speeds: 1650MHz for the GPU and 1800MHz real speed (7200MHz effective) for the memory. (Source: geeks3d)
[Update] the best way to cool your AMD Radeon 7970 is the Arctic Cooling Accelero Xtreme 7970 which will cool down your GPU for additional 10degrees celsius (at least). Overclocking, here we go!
Tonymacx86 showed how to Install OS X 10.7 Lion on any Supported Intel Core 2 or Core i based PC with xMove + MultiBeast. Furthermore, there is a Mac OSX Lion v10.7.2-HOTiSO that should also boot from any PC. Don't forget that you need to buy Apple Mac OS X Lion from the App Store to legally use it.
OS X Lion is the next major release of OS X, the world’s most advanced desktop operating system. It includes over 250 new features that will transform how you interact with your Mac. Built on a rock-solid UNIX foundation, OS X is engineered to take full advantage of the technologies in every new Mac. And to deliver the most intuitive and integrated computer experience. Brought to us by HOTiSO group. Mac OS X 10.7 was first shown to the public in October 2010. The presentation was understated, especially compared to the bold rhetoric that accompanied the launches of the iPhone (”Apple reinvents the phone”) and the iPad (”a magical and revolutionary device at an unbelievable price”). Instead, Steve Jobs simply called the new operating system “a sneak peek at where we’re going with Mac OS X.”
Its now possible to Install Mac OS X 10.7 Lion on your PC with the standard Hackintosh techniques. That means, everything stays the same to get your hackintosh up and running, no worries. More information on the geeknizer blog entry or alternatively, watch the video below:
Steps to install OSX Lion:
1. Get the "GM" (Golden Master) of Lion via torrent
2. Get an EFI Boot Loader
3. Get a decent 8GB USB thumb drive and install the Golden Master on there.
4. Install using iBoot.
You can get detailed information on installing Mac OSX Lion 10.7 by reading the geeknizer blog howto.
[UPDATE] tonymacx86 showed how to Install OS X 10.7 Lion on any Supported Intel Core 2 or Core i based PC with xMove + MultiBeast. Furthermore, there is a Mac OSX Lion v10.7.2-HOTiSO that should also boot from any PC. Don't forget that you need to buy Apple Mac OS X Lion from the App Store to legally use it.