New intel build, cant change BIOS without windows crash

[Spriggan85]

I am working on a new build for a friend. I have found the source of a previous issue, now after going into BIOS and trying to set the RAM to 1600Mhz, it was only reading it as 1333Mhz, Windows could not start or repair itself. This RAM is rated for 1866, yet I have read I5 3670k only recognizes 1600Mhz.
I have now installed windows 3 times, and I cant get the system stable. Im out of ideas and Im not an Intel fan. I have 0 builds with Intel, because Intel has always givin me problems, all my previous builds were AMD.

This system has:
Windows 7 64bit Home premium
Sabertooth Z77 (BIOS 1805)
i5-3570K Ivy Bridge
G.SKILL Trident 16GB 1866Mhz
Rosewill 1000 Watt PSU
Gigabyte R9 280X GPU

Is this setup not compatable? Is the root of my problem a driver or BIOS issue? What should I start with to stabilize the system? Im stuck and cant find many answers. I havent messed with BIOS since the 3rd install, but everytime I tried to change something it hasnt work out in my favor.

Also, when the system was stable initially I ran 3D Mark 11, and expected to get 30+ fps on extreme, I got 12fps. Can anyone give me an idea of what my problem(s) might be?

 

[sadams04]

You are only changing the memory settings when seeing the boot crashes? When increasing the frequency to 1600, what voltage and timings were you set at? Using an XMP profile? It could be as simple as your memory needing the right amount of voltage, or that the timings are off. For example, the GSkill Trident 2x8GB DDR3-1866 modules are listed at 1.6v. Perhaps you are set to 1.5v and at 1333 speeds they are fine...

If all settings (not just the frequency) check out then I would hit memtest86.com, download and burn a boot disk, boot to it, then make at least three passes to test the memory.