Btw I searched on google on extracting DSDT from Windows...and I was taken to a guide made by u "RehabMan" stating to use "read-write everything" application to extract the DSDT....will that work?
Yes.
Also there is also this app called Aid64 which also extracts DSDT and SSDT....so if I extract it from these particular apps then will it extract properly?
That will work too. As will Linux...
And I just have to take that DSDT and open it in my Mac DSDT Editor....but I don't know how to move forward from there...like do I have to select sandy bridge processor and patch it?
You can also extract your raw DSDT if you're able to get OS X running without a patched DSDT initially. Just run MaciASL and it will show you your native DSDT.
But I guess that's the issue is that you have the "reboot" problem when you attempt to boot the OS X installer. So now you're looking to DSDT edits... problem is you need to know what edits make sense, and usually you don't know those until you get the system running.
I assume you've tried all the flags suggested by the 10.8 install guide? PCIRootUID=0, npci=0x3000, GraphicsEnabler=No, -x, -v, busratio (don't ask me what that is for, I've never had to use it), DropSSDT=Yes, acpi=off, etc.
You could also play around with some of the kexts in /Extra/Extensions on the USB. There are some rollbacks there and some kexts which simply aren't neccesary to reach/use the installer. For example, AppleACPIPlatform.kext is from SL. And there is an IONetworkingFamily rollback (+ additional drivers), which, of course, you don't need to run the installer. You can rename them from *.kext to *.kext.bak to experiment.
Since mine is a Haswell-H processor variant I was not knowing how to move forward also My GPU is GTX770M so how to patch that too....
Haswell-H is a high wattage mobile CPU, right? Probably you'll be concerned about that when it comes time to implement power management (to be sure the SSDT generator has correct specs for your CPU).
As far as the 770M, most laptops with these graphics chips are using Optimus switching, and Optimus is not supported on OS X. You'll be trying to use the HD4400/HD4600/HD5000 (?) instead.
also I have to edit my DSDT on my other actual MacBook right...and not on ASUS laptop in which I am intending to install MAC...right?
That's what I would do. Use MacIASL. You'll want to spend some time with google trying to find others (who know what the heck they are doing and have a similar laptop) who are investigating DSDT edits for this kind of machine.
The DSDT editor now includes inbuilt patching facility but I don't know which patch to use....
Like I said, I would use MaciASL, and google for patches. To tell you the truth, I'm not sure what kind of problems cause a reboot during startup like that. From the descriptions I've been seeing (there are desktops exhibiting the same problem), it sounds like it might be a kernel issue. Fixing that would involve waiting until the kernel source is released and making some changes and/or adding additional debug output. Or even attaching a (remote) debugger to the kernel... but I'm not even sure how that is accomplished (beyond my skills).
One thing to keep in mind: Haswell is new. And OS X support for Haswell is even newer. Not everything is known about these systems regarding OS X compatibility. Source for the kernel has not been released by Apple, so much is not known and there is a lot to learn. People are still figuring out the finer points of Ivy Bridge and HD4000, as an example, and Ivy is more than a year old.