When we talk about large contact areas, specifically we mean motherboard chipsets, GPUs (Graphic Processing Units) such as the nVidia GeForce2 GTS and processor cores with large(r) contact areas such as the Intel Celeron PPGA and Intel Pentium 4.
Since Arctic Silver II has "support" for both small and large contact areas, Arctic Silver have discontinued the original Arctic Silver compound favoring Arctic Silver II which can then be promoted and sold as a thermal compound for all contact areas. The original Arctic Silver syringe included 6.5 grams of thermal compound, whereas Arctic Silver II now only includes 3 grams which is enough is enough compound to cover 20 to 30 small CPU cores, or 7 to 12 large CPU cores, or 3 to 6 heat plates according to Arctic Silver. Another interesting fact, at a layer of 0.003" thick, it will cover approximately 18 square inches. Because the syringes now only include 3 grams of thermal compound, Arctic Silver can now distribute the item at a much cheaper price, which can only be a good thing for us tweakers. Below is a picture of an original tube of Arctic Silver and a tube of Arctic Silver II for tube size comparison...
Arctic Silver II also brings us a new temperature range, -40 to 160c - This means that Arctic Silver is ideal for those that use extreme cooling methods, if your processor core is hitting 160c there's a good chance it would burn or melt, "Oh dear god no!" - Concerning thermoelectric coolers and Arctic Silver II, "Arctic Silver II was formulated to conduct heat, not electricity. It is only electrically conductive in a thin layer under extreme compression." Keep this in consideration if you plan to use Arctic Silver with a water cooling and peltier setup.
To test the different between the original Arctic Silver and Arctic Silver II we used an AMD Athlon 1GHz overclocked to 1.05GHz under load using a Hedgehog all copper heatsink. The temperature difference was nothing really to write home about, the Arctic Silver II was only one degree Celsius cooler than the original Arctic Silver - Remember though every degree makes a difference when we are talking about more overclockability. According to the Arctic Silver website and I quote, "2 to 7 degrees centigrade lower CPU temperatures than other thermal compounds." This may be true, however we cannot justify this until we actually test the same compounds Arctic Silver tested to make this claim. While testing the new thermal compound, I also noticed it was much easier to apply to the processor core, evenly. The new Arctic Silver II compound is runny (loose and more watery, if that makes any sense) compared to the original compound, which is just another advantage of this new compound.