"Simple" overclock of a I7 920 on P6T Deluxe

Well I finally decided I would do a bit of overclocking with my I7 920. I've got a massive copper heat-sink on the CPU, and I'm looking to get it somewhere between 3.6 and 4.0 GHz.

I did a quick test earlier and adjusted the blck speed and multiplier and CPU-Z is showing about 3.6 GHz when at full load. RealTemp showed some *very* high temperatures at 100% CPU load which has me quite worried. So I reverted to default settings. I've read that it isn't wise to keep the voltages set to auto, but the voltages are something that I'm very nervous about messing with myself.

So am I on the right track here or do I need to start doing stuff different? I'm not familar with the XMP mode and some of the other settings in the BIOS, what's the advantages and disadvantages of that?

Also, somewhat unrelated but is there any good tool to get precise information on the RAM in my PC? I've got 8GB total, all DDR3-1333 Corsair XMS3 series stuff, but there was some slight difference in the specifications that I'm worried will come back to bother me.