HT is just one core, but multi-threaded input to ensure the core is utilised 100%, rather than just 90% with 10% waiting for the rest of the system to ctach up.
Similarly, Dual Core has two seperate CPU's, but decreases performance due to delays with the shared IO that aren't present on a single core processor.
A factor of 1.7 should apply for x2 CPU's .. but oh well .. it's getting a bit complex
Alright .. lets see.
Turion x2 1.8Ghz Lappie = 3.6Ghz
Athlon x2 2.1Ghz Home Beast = 4.2Ghz
Athlon XP2100 -> 1733Mhz Home Server = 1.73Ghz
Athlon x2 2.0Ghz Work Beast = 4Ghz
Intel P4 3.0Ghz HT - Work Server = 3Ghz
Intel P4 2.8Ghz - Cad Server = 2.8Ghz
Intel P4 3.0Ghz HT - Cad PC 1 = 3Ghz
Intel P4 3.0Ghz HT - Cad PC 2 = 3Ghz
Intel P4 2.66Ghz - Work Machine 1 = 2.66Ghz
Intel P4 1.8Ghz - Work Machine 2 = 1.8Ghz
Intel PM 1.73Ghz - Work Machine 3 = 1.73Ghz
Intel C 1.0Ghz - Retired Work Lappie. = 1Ghz
Grand total = 32.52 Ghz.
But keeping in mind that the work PC's are only on 8-10hrs/day (and only 5days a week), and my home beast is only on maybe 4hrs/day, we need scaling factors
So I really end up with ....
14/24*3.6 + 4/24*4.2 + 1.73 + 10/24*5/7*( 4 +3+3+2.66+1.8+1.73) + 3 + 2.8 + 1 = 16.15 Ghz