Warning: Overclocking can potentially ruin components or shorten their lives. If you do it right (i.e. follow tutorials // read so you have an idea what settings/values your changing)... there is little risk if you keep voltages and temperatures within spec.
Your processor does overclock as it's an overclocking edition. 4.6ghz should be a breeze for it, closer you get to 5ghz you'll probably have to start really paying attention to the settings and know what voltage it likes... it's not a fast process done right. I can spend days to weeks OCing a CPU to get what I'd call "perfect"... and then start over a months later when I get the itch.
It's like a $50 CPU so if it melts who cares. Since it's made for OCing, why buy that model if you are going to waste it... :P :P
Problem is I bet your CPU has just the stock AMD cooler on it, which is a joke I'm sure. Keep an eye on your temperatures when you run the stress testing software... if it's at safe levels using stress tests then it'll be fine for gaming//everyday use.
I'm not a big RAM OC'er... but since you are using an APU, I'd be cranking on them to see if it matters to the results at all. Between a hefty CPU and RAM OC... I bet it'd be something atleast... night and day it will not be, think like 10%~20% boost to FPS.
Ideally getting a real graphics card to go with it would be good. $200~$250 range AMD cards would be a nice pairing I think. You could get an old 7xxx series (which the new series are just rebrand anyways) and do "hybrid-crossfire"... my limited experience with hybrid-crossfire was a joke but so was the APU I was using.
---------
Some of this might help, but again probably not much. Might even make it worse.
Open Notepad.
Copy and Paste this:
RenderDevice.ForceRenderAheadLimit 1
PerfOverlay.DrawGraph 0
PerfOverlay.DrawFps 1
PostProcess.DofMethod 0
PostProcess.BlurMethod 0
PostProcess.DynamicAOEnable 0
PostProcess.DynamicAOMethod 0
Render.VSyncFlashTestEnable 0
WorldRender.TransparencyShadowmapsEnable 0
WorldRender.MotionBlurEnable 0
WorldRender.MotionForceOn 0
WorldRender.SpotLightShadowmapEnable 0
WorldRender.SpotlightShadowmapResolution 256
WorldRender.LightTileCsPathEnable 0
RenderDevice.Dx11Enable 0
RenderDevice.Dx11Dot1Enable 0
RenderDevice.Dx11Dot1RuntimeEnable 0
RenderDevice.VSyncEnable 0
RenderDevice.TripleBufferingEnable 0
GameTime.MaxVariableFps 30
Save it as "user.cfg"
You cannot have user.cfg.txt
enable "View Extentions of Known File Types" from Folder Options in Control Panel
Put it in your PvZ directory
\\Origin Games\Plants vs Zombies Garden Warfare