Windows 7: which is better - GeForce GT 620 or 7950?

My girlfriend's sister may be looking at buying a new PC, but she really isn't that interested in gaming. She does some light gaming, like Peggle, ec. - and with her current PC with built-in graphics, even Peggle HD runs choppy. One of the PCs she's looking at is a MicroCenter brand PC which comes with an NVIDIA Geforce GT 620. Currently, I have a Geforce 7950 OC card sitting in the closet I could just give to her. Which is a better card for light gaming like she'll be doing - the GT 620 or my 7950? Because if mine is better there's a cheaper PC that comes with integrated Intel HD Graphics 4000 - maybe it could save her money if I'm just going to give her my card anyways. My 7950 is several years old so I imagine the 620 should be better, no? I just don't want her to buy a PC that comes with a card if I'm going to pull out the card anyways and replace it with one of mine. Then again I'm not certain my card will fit that pc:

http://microcenter.com/product/41330...sktop_Computer

Will the GT 620 be good enough for her needs in terms of light gaming? Also will it handle HD video and blu-ray playback okay? Her monitor is 1920x1080 so I just want to make sure she can play some of the types of games she likes without stuttering like her old PC does currently. She really doesn't want to spend a lot on a video card.

According to engadget, "The GT 620 is a GT 530 with a 49-watt TDP and twice as many CUDA cores as the 610 -- although a meager 64-bit memory bus will put a cap on any performance gains."

EDIT: hmm, it seems my 7950 says 350w minimum power supply - the PC I linked to comes with a 300w. I wonder if that 620 card at least performs as well as my 7950 - I assume it's certainly better than the Intel integrated graphics.

The GT620 should be perfect, the older 7950GT is a terrible choice since it's pretty much obsolete by modern standards. Moreover the 7 series GPUs was discontinued and moved to legacy status so there won't be any newer driver releases. The integrated HD4000 graphics is fine for general use but it's not gonna provide enough horsepower to drive modern games, you'll mostly likely experience lags and low fps.

Thanks, I had a feeling the 7950 was too old at this point to be useful. So then the 620 is at least going to perform better than the integrated HD4000 on the cheaper PC then?

Or let me ask another way - this PC for $599 has the integrated HD Graphics 4000 and the Intel Core i5-3330:

http://microcenter.com/product/40659...sktop_Computer

This one for $699 has the NVIDIA Geforce GT 620 Intel Core i5-3570K Processor 3.4GHz:

http://microcenter.com/product/41330...sktop_Computer

Other specs are similar (both have 8GB DDR3-1333 RAM). Which one would provide better performance for blu-ray playback and light gaming while keeping the resolution on 1920x1080 (like Peggle HD uses). Would the extra $100 be worth it for the 620 card and the Core i5-3570K?

Dedicated cards are better than any integrated solutions, the HD4000 might be able to handle some games at low-medium settings but don't expect too much. Both will more or less offer the same level of performance but the GT620 has the advantage of having dedicated video memory and this would be beneficial in certain situations where large amounts of textures are involved.

The HD4000 should be able to handle light gaming though. I'd suggest the $599 model.

I noticed the $699 model also has front USB3 ports unlike the $599 one where the only USB3 ports are on the back. Also I can't tell but it seems the $699 may have a 500w power supply vs the cheaper one which may have 300w? Not sure - both say 300w in the specs but the picture of the $699 PC clearly shows a 500w power supply inside the case, so I don't know what to make of that. If it comes with a 500w then I should be able to get her a better card in the future if necessary. If it's a 300w I don't see how any modern card can run on a 300w so she couldn't upgrade later if she wanted to.

I would go for the one with the i5 CPU and 620 GPU. You can't upgrade the lower priced one for the $100 difference.

I'd go for the HD 7750, it's more powerful than GT 620

OP, you limited to those 2 PC choices for some reason?
newegg has a build for sub $600 atm that would be better:

Newegg.com - Shell Shocker Deal. Exclusive Jaw Dropping Savings on PC Components and Electronics.

Albeit you would have to assemble.

I didn't see that as a choice.

I thought that too at first, op was referring to a 7950GT. However the HD 7750 is a better card:)