Power Requirements / New Power Supplies / Heat Sinks / Cases
Pentium 4 has got a rather large die, it runs at very high clock frequencies, it's got a rather long 'hyper-pipeline' and a supply voltage of 1.7 V. What does that all come down to? Yes, Pentium 4 needs a lot of power and is able to produce a lot of heat. This requires a good power supply and heat sink solution and because Intel is Intel, these things were properly taken care of.
Although Pentium 4 doesn't really need much more power than AMD's latest Athlon, Intel decided to avoid the mess that happened to Athlon-owners who used underpowered voltage supplies in their systems, resulting in frequent system failures. Intel is not following AMD's basically ignored compatibility list, which is hardly worth the paper its not written on, proven by e.g. Asus' A7V motherboard, which wasn't officially supported by AMD for a long time while AMD shipped review systems with exactly this board to the press. Intel is well-known for going ahead and establishing new industry standards, and as much as this may bug a lot of us who don't own the hardware required by the new standard, it assures that systems which accord to this guidelines will actually work without any glitches.
Pentium 4 requires a new kind of power supply that ensures the delivery of 10-12 A from the 12V line of the power supply. This results in the need for additional connectors that can carry this current. Although we managed to run all of our Pentium 4 test motherboards with a normal power supply as well, we encourage every Pentium 4 owner to ensure he's got one of the new power supplies that come with two additional connectors that need to be plugged into the motherboard. The two new power supplies available to us were from AOpen and Delta Electronics.