With your budget of ~$180, get the GTX 460 1GB version.
@ 1080p some people might say it's a questionable call, but I believe 1gb is such a superior card over the little brother.http://www.newegg.com/Product/Product.aspx?Item=N82E16814130596
($180 after MIR)
With this card (my card
), you can EASILY overclock it to 900 mhz core clock and probably more
I have it @900/1800/2000 and it idles around 38c and maxes around 80c, which is some great temps since these cards can go up to 105c
I was skeptical of the EE version at first but now I must say I am very happy with my decision, and I hope I gave you some viable options!