I see 83*F case temp and 85-90*F CPU temp at idle. at 90% load I have seen the CPU go to 103*. Unfortunately our upstairs AC unit struggles in the afternoon during the heatwave we are in, and the room gets up to 78*, and the computer temps go up to 90* and 97* at idle respectively. Basically I can count on case temp being about 10* above ambient at any given time. It is an Asus P4S800D-X board with a Northwood P4 2.2ghz, 2 512mb DDRAM sticks, 120gb SATA 1.5 OS drive, 80gb IDE backup drive, a CD burner, DVD Burner, Floppy/card reader combo drive, PCI Nvidia 256mb video card running two monitors, a wireless networking card and a K-world Video capture card w/tv tuner. PSU is a thermaltake 430w with dual fans. I think those are good temps, I just don't know because this is the first machine I've had that I could monitor temps with (this is basically a total rebuild of a Dell dimension). I run a 90mm rear case fan, an 80mm top case fan (both exhaust obviously), and an 80mm CPU fan. My biggest concern right now is the two HDs. They are at the bottom of the case, right behind the air intake, and there is 1 bay of space between them, but they get fairly hot to the touch. I don't have a measurement yet though. I'm considering putting in an 80mm intake fan to get some more cross flow over the drives first, before resorting to dedicated HD coolers.