CPU usage jumps to 50% when moving cursor around.

Why is your machine still Build 7600? Did you download and install all updates from windows update?

Installing updates is useful, as they fix bugs and security holes that may screw you over. May fix your issue as well, especially if you allow it to download drivers as well. Or maybe not. The only way is to try.
The difference between an unpatched XP and a fully patched XP was kind of obvious. With 7 is less evident but it's still recommended.

Frankly, if it is a hardware problem I'd suspect the mouse itself, not the processor, as all CPU malfunctions I know of have as main symptom "computer does not power up at all". Try with another mouse. And anyway clean the insides of the PC to remove any dust with compressed air as dust may cause overheating and overheating triggers safeties that degrade processor performance for the sake of keeping it cool enough to not die.

(moving mouse cursor does increase a bit the CPU activity, but not by that much even on my rig, that has a processor in the same general power range)

Thank you once again for getting back to me, Bobafett.

I used my old steelseries mouse instead of my razer lachesis to see if there was any difference to CPU usage when moving the cursor around, but it's still the same; CPU will jump to ~50% with the steelseries.

As for the temperature of the cores of the CPU, they're stable; they're at ~25 degrees when idle.

On a side note, I decided to pop out the Core temp program while playing one of my games, and the usage of both cores jumped up to nearly 90%! Nearly bottle neck. The temperature of the cores were still all right, sitting at around 35 degrees.

The game I was playing was Path of Exile, it's not even a game that's super demanding when it comes to hardware, it can run even on crappy computers. It runs okay on my machine, but has that occasional screen tearing that I described earlier in my post. Plus I wasn't even running it in full screen. The required PC specs can be found here Path of Exile System Requirements and Path of Exile requirements for PC Games

Is it normal that the CPU usage is this high while playing this game?


As for the windows update, I'll get around to get when my bandwidth resets, I'm almost at the cap right now. And the download drivers automatically was already in place this whole time.

Thanks!

Edit: I've looked more into the Path of exile game, and apparently, this game is very CPU-intensive. But I've played other games such as Awesomenauts which is a 2D game but still bottle necks my CPU, not sure if it's cpu-intensive as well, but meh...

for those two games I'd say it's normal. It's not the game that is CPU intensive, but the CPU that is weak.

The last thing, do you have Aero on? try turning it on if not and maybe doing this tutorial, especially step 6, and see if it improves.

Heh, this is the CPU list of the CPUs that can go on your current motherboard. Check the bios version that supports the CPUs in the list, if you want to upgrade, you may have to update ("flash") your bios as well.

this post has more info about choosing the best CPU.