Choosing a suitable graphics card for my system for mid-level gaming

[dons20]

Hey everyone, I need some assistance in choosing a good graphics card for my situation.

Ok so I have some friends on Steam and I realize that most of the interesting games there have graphics card requirements which is obvious to say the least. Now I have done some research as to the cards that would suit me well but I do like the NVIDIA PhysX feature so i'd prefer a GeForce card. I don't think I can spend more than $150 US on a card right now and would prefer to keep it as close to $100 if possible.

Here are my specs:

Processor: Intel Core 2 Duo E7200@ 2.53 GHz which I slightly clocked at 2.66GHz since I don't have a proper cooling case yet.
Motherboard: ASRock G31M-S (I may upgrade later since I want DDR3 memory)
HDD: 1 500 GB Seagate SATA HDD and another 120GB drive which was previously in there but is now failing.
PSU: 500W was what I saw when I last looked inside...

Preferred Websites: www.newegg.com, tigerdirect.com, amazon.com

I would like to be able to add a second card in Crossfire/SLI in the future, perhaps in the summer so take that into consideration.
The monitor I have is a CRT 16" and I usually run the resolution on 1152 * 864

Note that the graphics are Intel G31/33 Chipset and only have 64MB of Video Memory. This computer has done well with video playback as it has handled 1080p with relative ease and occasionally a lil stuttering but it runs fine.

I want to be able to play games such as Hitman: Absolution (I won this game in a giveaway and badly wanna play it!), Team Fortress 2, DOTA 2, League of Legends, Magicka among others, and I need a good graphics card to play those games on low to mid settings.

Please recommend any cards you think will do the job. I don't need a NVIDIA card specifically but I do like the PhysX feature as I said...Thanks!

Oh and I was looking at this card as well... ASUS GTX 550 Ti (Fermi)

 

[Onus]

On a modest budget, wanting only low-mid settings, a $110 GTX650 would do, but a $140 GTX650Ti would give you much better performance.
If your budget is super-tight, a $60-$70 GT440/GT640 can probably play these on low settings.

Make sure your PSU is up to the task. If you've got a cheap generic that came with your case, if it has a PCIe power connector you can probably run a GTX650 on it; if it doesn't, get a HD7750. You'll lose PhysX, but actually get comparable or slightly better performance. If your budget allows, $40 will buy an Antec VP-450, which can run any of these (or some stronger) cards.

 

[swifty_morgan]

maybe a gt640? your resolution is low so there really isn't a need for a big banger.

your processor will hold you back some. no need to get a board, if you can find one, that will run DDR3 ram. I still game mostly with ddr2/800.

 

[Onus]

Hmmm, missed your edits...
Crossfire is for AMD cards; SLI for nVidia. Running a pair of weaker cards pretty much never makes sense compared to running a single stronger card.
At your resolution, get a GTX650. Most of them require a PCIe power connector, but Asus has one that does not. Get that one: http://www.newegg.com/Product/Product.aspx?Item=N82E16814121710 for $115; $105 if you play the rebate game and win.

 

[nukemaster]

Lucky for you your cpu is a lower power model.

I am with Onus on checking the power supply. See if you can get an image of the sticker or at least the specs. The +12volt rail is the important one. If you have more then one, you will want to look for a combined rating. It may look something like this.

OR
This. wattage / voltage = amps so 288/12 = 24 amps

All in all, you can NEVER have to much video power. Get the best your can afford and power.

 

[dons20]

Lucky for you your cpu is a lower power model.

I am with Onus on checking the power supply. See if you can get an image of the sticker or at least the specs. The +12volt rail is the important one. If you have more then one, you will want to look for a combined rating. It may look something like this.
http://imageshack.us/a/img829/7152/psur.jpg
OR
This. wattage / voltage = amps so 288/12 = 24 amps
http://img560.imageshack.us/img560/4529/multirail.jpg

All in all, you can NEVER have to much video power. Get the best your can afford and power.

Ok I just looked at my PSU, yes I believe it is a generic one that came with the case. My father was the one who firstly set it up. It actually says ATX-400 and underneath that the +12V rail is 18A. I can't get a picture just yet, perhaps by tomorrow. Does this mean my PSU is actually 400W not 500?

 

[dons20]

Best answer selected by dons20.