Certainly your processor will create some serious bottleneck even if you overclock it!!You should get a core 2 quad or phenomII x4 to squeeze the power from a 5850!!But still you can expect a great level of performance from a 5850 with your current cpu...Most of the games except crysis and gta4 should do well with a core2 duo...To get maximum performance out of your card you must upgrade the cpu
Yeah, that's waaaaay more card than you need at that resolution. Only consider it if you are also going to be upgrading your monitor to one with a native resolution of 1920x1080 or higher sometime in the near future. If not save a ton of money and grab an HD5770 although an HD4850/5750 would be quite good for you current monitor as well.
Of course you will have a bottleneck, just like every other system on the planet. You will just see more of a bottleneck at your CPU than in a system with a faster CPU or more cores. Your resolution is not that high so a 5850 may be a little overboard unless your games are really GPU demanding. If you are looking to upgrade your monitor (ie resolution) it might be a wise buy. But if you are sticking with what you have, you may want to wait until the 5830 shows up. It was supposed to launch on the 25th but I think it s now Feb 5th. It should offer performance between the 5770 and 5850. It might be a wiser purchase. You can always use the extra month to toss in a quad core or just save for a mobo,cpu,ram replacement down the road. Just my thoughts. a 5850 is alot of card for 1366x768
You will get 4 cores at 2.33MHz. In games and apps that take advantage of 4 cores you will definitely see improvement. However, if a game doesn't scale well with multiple cores, you make not see anything. I would really just stick with your CPU and wait until you can upgrade to the latest architecture, i3,i5,i7 CPU. Unless you can get a quad core cheap.
If I buy a Quad Core 8200 and dont change the monitor will their be no bottleknecks
I'm not sure there's a processor in existence that wont bottleneck that card at that resolution. The HD5850 is extremely overpowered for that resolution so the limit will always be the processor in most games. Like I said earlier unless you are going to upgrade your monitor the HD5770 is really the most powerful card you should be considering. You can than use the money you saved to get a good quad core but really you can just overclock the e5200. It OCs easily and well. You should be able to get it up to 3.3-3.5 ghz just on the stock cooling and at that speed it will be a pretty nice processor for gaming.