So about half a year ago I bought a computer from a store, not really knowing how much I could save by putting it together myself piece by piece. It's already quickly getting outdated which is why I'm looking to upgrade the video card (PCI-e 2.0 x16 slot), to keep up with the new game releases and their increasing reqs to use decent settings.
Current specs for reference:
Motherboard: Micro-Star D2415
CPU: Intel Core i3 550 @ 3.2GHz (4Mb Cache)
Graph Card: Ati HD 5670 (1Gb VRam)
Memory: 8 Gb
Browsing through the different alternatives I ended up being interested in GTX 480 (link), a high-end graphics card that still has a relatively affordable price, but I'm concerned over a couple problems it might cause to a computer that really wasn't designed to be used with great parts: CPU bottlenecks and electricity consumption.
About the CPU bottlenecking the performance.
It's going to slow things down a bit but upgrading the bad CPU is so expensive that I'd avoid it by all means if possible, since upgrading to a new processor suddenly doubles the cash spent on upgrading. Intel Core i3 550 (overclocked) is however so likely to be outclassed in this company that I'd like to get a recommendation on a CPU to buy and alternatively a suggestion on another video card that wouldn't be a waste with this processor, assuming that the current setup wouldn't make sense.
Increased power consumption.
The box computer didn't come with the space for a power supply located inside of the case. Either this means that a) I need to find another way to get extra power, b) I need to buy a new computer case and re-assemble everything inside of it or c) I have to find another video card to get which remains within the boundaries of the power available now. Since HD 5670 uses up less than 75 watts it seems likely there's need for extra power with all of the new video cards. The only information that I managed to find about the current power source was here, as follows, "Max. output of single power supply 330 W" and that wouldn't be enough for any of the new video cards not to even mention powering up the processor as well.
In all, I think getting a new case for the additional power supply, then a video card is my best option. Are there any problems that I don't know about that the experts here see?
Thanks for the help!