Although a motherboard, BIOS, CPU and a capable operating system such as Windows XP is required to utilize Hyper-Threading, the 3.06GHz Pentium 4 was the first processor from Intel to support it, it will still operate in a non-HT system problem free, you just don't have Hyper Threading enabled then.
All Pentium 4 class C (800 MHz FSB) processors have support for Hyper-Threading, your mainboard must support it also though.
The task manager 'performance' tab whows clearly that Hyper-Threading is enabled, just look at the two graphs.
Many of the latest motherboards out there on the market are now featuring dual-channel DDR400 support. Intel Springdale and Canterwood mainboard are the first of the chipsets to support dual-channel DDR400 for the Intel platform with a theoretical total of 6.4 GB/s of memory bandwidth, others like SiS and VIA have chipsets either development or already support both DDR400 and pretty soon the 800MHz FSB bus.
Multiplier 16 times 200MHz FSB = 3.2 GHz
The Pentium 4 3.2 GHz processor runs at a core voltage of 1.550V. This somewhat higher Voltage compared to the class A & B generation was necessary to justify the higher clock speed and thus stability. Not too worry though, the CPU remains level at an all-time very cool temperature. We stressed the CPU a lot and it never even topped ~60 degrees C, in idle you can expect about 40-45 degrees C.
The voltage increase by definition does not mean you need a newer mainboard, a BIOS upgrade would suffice in most circumstances, even the most 845 chipsets are capable of running this CPU with 800 MHz FSB after a BIOS upgrade. Check this with your mainboard manufacturer before considering this though. The thing you need to bare in mind is that your mainboard must support the 800 MHz FSB, otherwise you'll need a new mainboard. Funnily enough it now uses quite a lot of power, in fact enough to light a very bright bulb at ~82 Watts when it peaks.