I was planning on getting this graphics card for my PC
http://www.amazon.com/MSI-R7-260X-DisplayPort-PCI-Express/dp/B00FR6XOQO/ref=sr_1_2?ie=UTF8&qid=1404709549&sr=8-2&keywords=msi+r7+260x
I was going to get a 500W power supply for it and a friend was going to get me his old case. I need to know if my motherboard can handle the power supply or if I needed to buy a new one.
The Power supply is this one - http://www.amazon.com/EVGA-80PLUS-Bronze-Certified-100-B1-0500-KR/dp/B00DGHKK7M/ref=sr_1_1?ie=UTF8&qid=1404716723&sr=8-1&keywords=bronze+certified+power+supply
My PC is this - http://www.amazon.com/eMachines-Athlon-2-8GHz-Desktop-EL1358G-51W/dp/B0060N07JK/ref=sr_1_1?ie=UTF8&qid=1404716639&sr=8-1&keywords=eMachines+EL1358G-51w-+Athlon+II+X2
It looks like it should be fine. As far as I know, and I don't know much mind you, the maximum capacity of a power supply has no impact whatsoever on components, so long as it is above what it needs to be.
Open up the the eMachine and just check just in case if there is a PCIe port. Also you can use Piriform's speccy software to find out what motherboard you have.
Also the Athlon II is a socket AM3, that way if you ever need a different motherboard you know what to look for.
What type of case are you getting from your friend?
The Case is this one - http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=1709407&Sku=U12-41933
Will my motherboard fir it correctly?
Mini ITX, mATX and ATX should fit a mid tower.
I would not use that power supply that comes with the case though. They are usually of questionable quality and have a tendency to fail. But your mileage may very, as I have only read about PSUs with cases. Make sure to read the reviews, they also mentioned the PSU failing.
Alternatively, pick up a 750ti and you shouldn't need a power supply upgrade.
http://www.amazon.com/PNY-2048MB-Graphics-Cards-VCGGTX750T2XPB/dp/B00IGHD876/ref=sr_1_17?s=pc&ie=UTF8&qid=1405025434&sr=1-17&keywords=r7+265
I would try to pick up a R9 270, it tends to be around the 150-180 price range, and has more performance than the R7 260x.
Here's one I found for cheap.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814202090&cm_re=R9_270-_-14-202-090-_-Product
Thanks for all the help guys. Everything you told me helped me tremendously.