I am running FSX on a machine with following: Intel Pentium 4 630, 3.00 GHZ ASUS P5S800-VM motherboard, 1022 MB ram ATI Radeon 9550 video (secondary AGP) 256MB memory, 250MHZ DirectX 9.0cwith most sliders set in the middle, I am getting between 3 and 20fps; turning view is very jerky; spot plane jumps all over the screen; unexpected fluctuations in framerate - for example, on ils approach I may be getting 15fps but every now and then a stutter and drop to 5fps for no apparent reason!I have even tried with autogen scenery OFF -- still same problem...BUT what really puzzles me is that throughout Windows Task Manager shows that cpu usage never rises above 55%. What is happening to all that other computing power? What am I doing wrong???any suggestions most welcome.Ron

>BUT what really puzzles me is that throughout Windows Task>Manager shows that cpu usage never rises above 55%. What is>happening to all that other computing power? What am I doing>wrong???>If you have a dual-core cpu, that is completely normal. 50-55% is the normal usage in FS. So that computing power is being wasted, in essence. That is why the fast single core cpu's do so well in FS.RhettAMD 3700+ (@2.5 ghz), eVGA 7800GT 256 (94.47), ASUS A8N-E, PC Power 510 SLI, 2 GB Corsair XMS 3-3-3-8, WD 250 gig 7200 rpm SATA2, CoolerMaster Praetorian