I recently upgraded my PC's motherboard, and before my CPU use to idle at around 43C (Its a Prescott based Celeron D, 2.66Ghz) but now it idles between 45 and 50, I've applied the thermal compound twice now, and the first time I beleive I had it too thin so I re-applied it only this time using the Arctic Silver creamique way and put a small dab in the middle near the core and then put the heatsink over it, and moved the heatsink just a few notches to the right and left to even it out and remove air bubble, and now it idles at around 42-49c, whats the normal operating temperature for a Prescott based Celeron? Do these temperatures sound normal?

Well, nevermind that, after running for another few minutes its now at 53-55C idle, after turning the system off and unplugging when touching the heatsink it is hot, so I know I must be getting good transfer? maybe the temperature sensors are off? it says the system temp is 24C.

And if it helps, I'm just using cheap radioshack thermal compound. (yes, I know, I should've gotten better but it was the only stuff I could find around here and I need a PC running, I plan on replacing it later with something better. Though I do not know when at this time.)

You're complaining about a couple of degrees difference? It could simply be a difference in sensors. BTW, Radio Shack thermal paste is fine

ASUS A7N8X-X
Athlon XP 1800+
8.5 x 200MHz
1024MB PC3200 2.5-3-3-7
Asus A9550GE/TD 128MB
WinME/WinXP Pro SP2

just making sure if you cleaned the residue of your old thermal grease before reapplying!