The CPU is 3 generations old and not even a good one from that generation. The GPU is the slowest direct X11 card Nvidia make and its only sold to big PC builders like Dell & HP and is not for sale separately. You will not be able to play power hungry modern games like Crysis 2 or Metro 2011 at all you may be able to play less demanding modern games on lowest settings and resolution. If you got a better graphics card (which may need a better PSU) then you should be able to play non demanding games on medium settings but if you want a gaming PC then take it back and start again. From the specs I think it must just have been about the cheapest PC for sale new, if not I suggest you return it for a refund.
What do you mean good or bad?The correct term is new or old architecture.Good or bad brand name and depends on manufacturer for the material quality of the components.I was looking for a graphics card from ebay and there was a new one from china that was cheaper than the one from uk.I dont know if i am wrong or not but i think many pc components that are very cheap they are not durable.
It was a very bad buy.
Those specs are quite old, they shouldnt even sell it anymore.
Its quite hard to upgrade from that build because of compatibility issues.
I think you just start from scratch and build a much future-proof-ish type of rig.
instead of using GT420, you'd be better using GT440 DDR5 from Digital alliance,
its cheap but strong enough to play Tomb Raider 2013, BF3, COD etc
its clock quite high, and i used it a few years ago, benchmarking using combuster got quite high FPS http://www.digitalalliance.co.id/product/graphic-card/n...
processor you could use E7xxx series, you could search a second-used,
mysuggest : better to upgrade your pc before everything too late, and expense more money, you could use AMD and ATI for the cheaper ones