Hi, I've a question about the way the processor handles multiple jobs at the same time. I don't know if this is the correct forum to ask, but I give it a try. Suppose that two applications A and B are starting at the same time. Suppose that application A requires 40% cpu when application A is the only active job on your system and application B requires 70% cpu when application B is the only job on the system. Now, when starting app. A and B at the same time, there has to happen something. The sum of the %cpu is equal to 110%, but the processor can't get higher than 100%. So, my question is what happens? I don't know it. I can imagine two possible options, which are: 1) Both applications get 50% (100%/#jobs), but since app. A only requires 40%, app. A gets 40% cpu and app. B gets 60% cpu. So, in this situation only app. B is starting up slower. 2) The total required cpu percentage is 110%, so each job get a fraction 100/110 of his original cpu percentage. For application A it would be 36.36% and for appl. B it would be 63.63%. The percentages summing up to 100%. In this situation, both application are starting up slower. Next question that arises: What happens with streaming audio/video? In situation 2 all the jobs would get a lower speed, hence the audio/video won't be played smoothly anymore. In situation 1 this is highly dependent on the number of simultaneous jobs. So, I think that my first thought (situation 1) is the way the processor handles simultaneous jobs. Is there someone who can give me some information about it? Thanks.

Before you think about that question, does your P4 support Hyperthreading? If no, then the program will be processed based on whatever program opened first. If your CPU support HT, then for every cycle it requires to process this software, let say 40% of cpu ultiization, then the free 60% will be used to process the other program.. So it will be like X = Program 1, Y = Program 2 W/o HT X Y X Y X Y X Y X Y X Y X X Y X Y With HT Y Y Y Y Y Y Y Y Y X X X X X X X X X X X X Your CPU is limited to 100%, if there is no more room to jam in the data, then you will have to wait for the next availiable cycle.. Like P1 use 40% and opened first, P2 need 70%, but P1 will be process first and during the mean time you open P2, it will give you the 60% left for P2 to use, resulting P2 open slower than before. Also don't forget that you are loading those program first from the hard drive, running 10mb/sec w/o cached, resulting both program running even slower... If you really concern doing multi-tasking, either get a P4 with Hyperthreading, dual-core w/o HT, dual-core with HT or an AMD CPU with dual-core. That way you can do multi-tasking w/o losing performances.. X = program 1 Y = program 2 C1 = CPU1, C2 = CPU2 1CPU w/o HT X X X Y Y X Y X Y X Y Y X X 1CPU w/ HT Y Y Y Y Y Y X X X X X X X X X 2CPU w/o HT CPU 1 X X X X X X X X CPU 2 Y Y Y Y Y Y 2CPU w/ HT CPU 1 Y Y Y Y X X X X X CPU 2 Y Y Y Y X X X X X Hopefully that helps.. TMP-Man Asus P5P800-SE Pentium 4 506 2.66Ghz @ 4000Mhz @ 1.5125v 1024MB Dual Channel DDR400 40GB 5400RPM + 120GB 7200RPM HD 128MB Radoen 9500 mod 9700 @ 360/585