giong 1700+ on 1333 rated fsb dangerous?

what ram do u have?

Its dangerous when you use too much voltage and the chipset gets too hot.

(stock) E6600 = 2.4GHz / 266FSB = 9 CPU multiplier.
(your overclocked) E6600 = 3.4GHz / 9 = 378 FSB. (1.51GHz effective.)
1700 / 4 = 425 true FSB.
425 * 2 DDR = 850.

So now that the math is done, I don't quite understand. You have DDR2-850MHZ ram? If you have DDR2-800, you need an FSB of 400/1600. If you have DDR2-1066, then you need an FSB of 533/2132. Where does the 1700+ figure come from?

If you have DDR2-800MHz, sync the ram and FSB to 1:1. Put the FSB to 400, and put the CPU multiplier as high as it stably goes. (9 if possible, if not, drop to 8.) If you have DDR2-1066, do the same thing, but try to tighten the timings of the ram.

The only problem you'll have with your board is the possible data corruption that happens sometimes with Nvidia boards while overclocking. The 780i should be able to overclock to 400MHz just fine. Just keep an image handy of your OS/data.

Edit in bold.

My vote doesn't change. (sorry, I typed DDR2-800 twice last time.) Set the FSB to 400, leave the multiplier at 9 if possible, 8 if not, and set the FSB:RAM ratio to 1:1. Seeing as you have DDR2-1066, you can try to get lower then 4-4-4-12, but I'm not sure if thats possible. (its not if your memory is already at 2.2V) You have an Intel CPU, so fast memory isn't really needed.

Seeing as you have DDR2-1066, you can leave the memory at 1:1, and try to raise the FSB. If you can get it as high as 500, you'll nearly be stock for that memory. The CPU will have to go to 8, and possibly 7, but it will still be quite fast. I don't think I'd go very far on the FSB however, I'm a wuss with Nvidia overclocks.