It would help someone willing to help you if you provide information if there are any software or not that you use in obtaining those temperature values.
So much more info needed, what CPU cooler are you using? What type of fan control software are you using? Any OC of CPU? CPU power saving options enabled in BIOS? Have you manually set CPU voltage? What mother board do you have?
The 48-50c is just with windows 7 pro 64bit running off of a fresh install. I have no background applications running. I have not installed any anti-virus software or the likes as of yet.
As soon as I load up World of Warcraft, the temps shoot up to 60-70 C (Core Temp is showing these temps with 28-35% load on the CPU, which seem rather high). With the stock thermal paste I was seeing 72-75 C, so the Arctic Silver 5 has helped quite a bit. It's still concerning to see such high temperatures, as I've been told I should be idling 35-38 C in Windows.
If there is information I can provide to help narrow down the issue I'd be more than happy to.
When playing a game you always expect the temp to shoot up. I do get those values while playing DIRT3. At idle my temp range is from 34 - 50 C. I'm just using the included thermal pad of the cpu. I use OpenHardwareMonitor-an open source program to obtain those values. If you go to your bios you should be able to get the value of the processor temp also.
Check your casing ventilation. Perhaps you can still lower your idle temp a little.
To answer your question: It could be the normal idle temp of your system. (48-50C). 60-70 C while playing a game is normal. You still have other options to improve the cooling sytem of your unit.