Hi I'm new here and haven't dealt with PCs for some years now. I have an HP 3130 MT and I have a PCI-e slot and I'm looking to upgrade it to play games. I am interested in the AMD Radeon 6950. My processor is the Core I5 3.2 ghz. I'm looking to upgrade my ram to G.SKILL Ripjaws X Series 16GB (4 x 4GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Desktop Memory Model F3-10666CL7Q-16GBXH. Is this a waste since the bus only supports 1066? Also will the video card work in my system?
Ok first off do you have Windows 64bit or 32bit. If you do not have access to 64bit, you can not use anymore than 4GB of ram (actually closer to 3.5). For gaming there really isn't any need for more than 8GB total. It looks like you can put in 1333Mhz ram, but you ma or may not be able to have it run any higher than 1066, I am not sure.
That PC is in a mini case correct. Make sure you measure the dimensions of the available space for the graphics card. You may have fit issues depending on the size of the graphics card. The graphics card other than pure size, will fit.
You don't need 16gb for playing games , you can use 8gb and be just fine. Is your cpu , the Intel i5 650 ? It looks like that video card will work for you , but before you buy it you want to measure the inside of your case to make sure it will fit. Sometimes the video cards can be quite long and if you have a small case there could be problems fitting it in.
There isn't a disadvantage of having 16GB of ram verses 8GB, other than paying more. The $35-45 you would spend on the extra 8GB would be better spent on a better graphics card, or a higher quality psu. The other option would be to spend the money saved on some general case fans, to help with cooling. I would actually suggest doing that, since the graphics card is going to put out a ton of heat in comparison to integrated. If your case doesn't have enough slots for fans, you could get a fan that fits into a pci slot, that exhausts air out the pci slot. You would put that below your graphics card. I'm not too sure how well they work since I haven't used one before, but they seem like they could be useful.
(1) your power supply is either a 250 watt or a 300 watt depending on region. That won't power a Radeon HD6950. I didn't see anything that would give the form factor of the PSU (e.g ATX or SFF or...)
(2) The case is listed as 'microtower'. Does it have full height PCIe slots? How long can a card be and still fit in the case? What kind of cooling does the case have. Typically prebuilt systems with small cases cannot be made into strong gaming systems unless they are designed for that use up front, but from the specs this case seems like it might be a 'mini' not a micro. As the video cards get stronger they get longer and need more clearance for poweer cords, etc.
(3) The processor is plenty strong enough to game.