Agree with NV. The TDP and base clock on that chip are relatively low, which won't leave you room to maximize performance if you choose to. $150 can probably be trimmed from a custom rig to make it happen.
Without even trying, here's something that will fit the budget:
http://www.newegg.com/Product/ComboBundleDetails.aspx?ItemList=Combo.1327042&cm_sp=DIY_PC_Combos-_-1327042-_-Combo
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130827
$723 total before shipping and about $643 after mail-in rebates. Doesn't include monitors and all of that stuff, but you can easily squeeze in a keyboard and mouse with that $80 in rebates. Your ASUS linked above doesn't come with a monitor either.
If you priced the components separately you might be able to do even better.
Without even trying, here's something that will fit the budget:
http://www.newegg.com/Product/ComboBundleDetails.aspx?ItemList=Combo.1327042&cm_sp=DIY_PC_Combos-_-1327042-_-Combo
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130827
$723 total before shipping and about $643 after mail-in rebates. Doesn't include monitors and all of that stuff, but you can easily squeeze in a keyboard and mouse with that $80 in rebates. Your ASUS linked above doesn't come with a monitor either.
If you priced the components separately you might be able to do even better.