which card?

[j.col]

hi guys,
my kids pc has a hd 4770 (512mb ddr5)
my pc has a hd 3870x2 (1gb ddr3)

on tomshardware site, the 3870x2 is in a higher tier than the hd 4770, but i have noticed, most of the games i play are only using 1 core on the gpu.

the kids aren't using their pc anymore, so i want to get rid of one.
which would you get rid of?

kids pc only has an old P4 3.0GHz cpu, 2Gb ram.
my pc has only a E3300 overclocked to 3.0GHz and 2 gb ram.

i might just get rid of both. and buy a decent gpu.
but for now, which one to get rid of?

 

[j.col]

thanks guys, guess its time to run some benchmarks.

 

[j.col]

thanks guys.
i will probably get rid of both and get a better one,
but i will need to upgrade cpu as well

@opethdisciple
i put the fan on 70% while gaming, and the card never goes over 40.C
also i have a corsair hx 520w psu

@95thrifles thanks for the info, i had an idea about the first number, but that was perfect.