Hey guys, I have had an Asus g60jx laptop since about 2010 and I'm trying to squeeze as much life as I can get out of it in order to get the biggest upgrade possible for my next laptop. I'm considering upgrading the processor from an i5 430m to the i7 820qm as I see they're around $100 bucks on ebay. Would you guys mind telling me how much of a performance boost I'm likely to see in games, if any?
i7 820QM "Clarksfield" is about 30% faster using 1~4 thread tasks, and about 60~ 70% faster using all 8 virtual cores. So I think the upgrade may be worth it depending on what you want to do, as long as it is possible to do.
Just make sure to double check your mobo is compatible to the older generation "Clarksfield" cpu. Although both are based on Nehalem architecture, your i5 "Arrandale" was targeted for lower end market, thus was slower, but cheaper and lower power consuming than the older "Clarkfield."
Also, i7 820QM has no iGPU, so you may be out of luck if your system has no dedicated gpu to use.
Get something like an i7 640m or 620m or i5 580m etc as these cpus are arrandale 32mn dual cores with igpu great for laptops. I would not downgrade to an i7 820qm as you are basically paying more for ancient technology which is slower at singlethreaded stuff and will heat up your laptop a lot as these cpus take 30w more for what 10% gain in multithreaded performance compared to lets say a dual core i7 640m.
Actually, if I remember correctly Arrandale is slower than the older Clarksfield clock for clock AND with full thread count, especially since Arrandale i7 is a dual core (i7 Arrandale = dual core w/ HT, i7 Clarksfield = quad core w/HT). The power, heat, & compatibility issues aside, if the mobo allows I think Clarksfield is a better choice. If the mobo only takes Arrandale, the OP has not much choice, and I say don't upgrade, and just sell the laptop to buy IVB or Haswell i7 laptop at a later time.