upgrade imac mid-2010 27" core i3 3.2

[ionicle]

hello!
not posted on here for a while ...or ever in the mac section lol
i have a mid 2010 imac, and while its brilliant, it is starting (only just mindya) to show its age...
i have ordered a 2x4Gb kit of DDR3-1333 SODIMM's to upgrade it, and im sure that will help, but i feel the slowness is more of a processor thing than a ram thing (although memory clean frequently reports that i have 100mb, 50mb, or sometimes even just 3,5,7mb of free ram at any one time)
so i had a look on iFixIt and found i need a intel core ...something 1156 ...it recomended an i7 which when i looked at the price (about 300 quid) thought, naff that one...

its been a few years since ive done anything majorly techy (hense the imac) and the last time i was TRUELY into computers, the choise was a simple one, do you want the fast and wonderful Athlon 64, or the slow and crap pentium 4 with HT

since then ive kept an eye on whats gone on, but not really paid too much attention...i built a bulldozer system a few years back and its gathering dust at my grans house in the spare room, because im a definate mac convert now...

any advice would be appreciated, spec below:

iMac
27"
Mid 2010
Core i3 3.2GHz
4Gb DDR3-1333 (soon to be 8, wanted 12, but on a budget)
1Tb HDD (replaced by apple after the big HDD scare)

This is what the google search came up with:
http://www.ifixit.com/Guide/Upgrade+...o+Core+i7/8670


Any direction-pointing would be appreciated, im not entirely sure where i would like to take it, but quad core would be nice..., thanks

[CAT-THE-FIFTH]

Ebay should have secondhand socket 1156 Core i5 and Core i7 CPUs available.

[watercooled]

On the subject of memory, don't worry purely about lack of 'free' memory - operating systems will, for example, cache recently used files/applications in memory so you can access them more quickly. Although this subtracts from the 'free' value, it's still easily accessibly by anything which needs to allocate RAM.

Memory clean sounds like another one of those nonsense apps written by devs who either don't understand basic memory management principles, or just deliberately mislead users for whatever reason. For reasons I explained above, it probably does more harm than good. I doubt some random free app with no system access besides issuing a purge command will know or be able to 'optimise' memory management better than the Apple/Unix.