... System Idle is there to show you how much is free for your processor... I doesn't actually use that power.

Well, I leaned something new, if that's true though.
Why would it show up in use on Task Manager, but not really be in use?

Because it shows you how many percentage is left to use.

Why do you think it drops when the CPU is being used? Yeah.

The system idle on windows should take at most 5% of your CPU on a bad day, that's just because you have a ****** computer. If you downloaded a bunch of **** onto it then yeah it'll do that. Try running a defrag and delete old unused files.

And 15% is still alot of CPU.

Meh. I just have a Athlon II x2 260 Regor in this thing, with that CPU usage, I don't see any noticeable degradation in performance, 10% - 30% usage of each core with that process, currently only 51 processes running.
I have noticed that System Idle Process drops considerably during CPU-intensive programs like 3DS Max, or games, so it's not always up there at 80 processes.
Also, that's not percentage, that's processes, 15 processes is considerably small.

In a way, they are percentages, since a process consuming 0.9% of CPU would show up as 00 on task manager, since task manger rounds processes off into a double-digit format.
Also, I found this:
"The System Idle Process is the first process that is created when Windows is loaded, and it always has a process ID of 0. There is one thread in the System Idle Process for each CPU in the system. When the CPU has no other work to do, the Windows scheduler selects the CPU's corresponding idle thread for execution. The accumulated CPU time of this process therefore shows the total CPU time that has not been used."
No wounder that ****** noms all them processes, especially when my CPU is just laxin'.

So how many programs did you download again? Perhaps a desktop screenshot?...

Everything is set to not start on System Startup, excluding Rainmeter, because I love that **** .

Hidden Processes? How much RAM capacity do you have left?

Desktop below this post (currently), and how would one show Hidden Processes? I know Task Manager shows almost everything, but not all processes.
My RAM is 4GB Physical and 8GB Pagefile in this 64-Bit Windows 7 Installation.
1.74GB / 8GB of Pagefile (SWAP) RAM in in use and;
1.57GB / 4GB of Physical RAM is in use.

Probably a virus then, possibly malignant. Any third-party/obscure open-source software downloads?

The virus would be hidden from all process/data readers, you'd want to run a scan with at least two security softwares (probably windows defender and mcafee/norton)(not at the same time, though, they'll attack each other). Then once the problem(s) were identified, use ************ first to delete the file. If that does not fix the problem, try the security repair processes.

It could also be a result of one program that has alot of communications and/or readers. Try disabling Rainmeter and see if that works, much as it might pain you.

Wait, wait, wait.
When did this turn into a virus discussion?
I know my system is clean, nowhere did I mention my system was bogged down, or I suspected I had a virus.

Viruses don't always bog a pc down, but it could be doing some **** inside your computer. If it's there at all. And that's generally an accepted explanation for "lots of processes are running but I've disabled everything."
I don't know, if you don't think you have one, don't bother and just try disabling Rainmeter. Other than that I'm not a technomancer so the only further piece of advice left in my frail mind is delete system32

I'm the go-to PC guy and the Network administrator for my family, and 51 total processes is fairly small since the PC in the family room that everyone abuses has somewhere around 70 running.
Also if I see a program I see as useful in the future, but it looks sketchy/never heard of it, I search around the net for other people's experiences and if good, I am sure to get it from the main/legit source ( Web Of Trust plugin for Firefox helps steer me away from bad sites aswell ).
I still don't see where I mentioned my system being slowed, suspecting I had a virus, or saying my processes were too damn high.

Again, it was a preventative action bit of advice and a scan certainly couldn't hurt the computer
The processes just seemed high to me I guess
The only programs I really run don't do anything in the background, and the only things that do are the preloaded skydrive **** that comes with windows 8
Carry on then, sorry for disturbing your peace

Skydrive, isn't that one of those Cloud services?
And I scan it at least once a week, only thing that comes up with Malwarebytes is the loader I got for GTAIV a couple years back so I don't have to always load in the disk. I also use Avast! as my main Anti-Virus, Malwarebytes just sits there until **** gets real.

Yeah it is, and a ****** one at that, although it does come in handy for recovering lost files.
In that case okay. I just saw the other comment about system idle too. Good day fine sir.

I've never really liked the cloud, but no jewgolds to get a 1TB external for a backup.
Ciao my good sir.
.gif unrelated.

Forgot Screenshot.