Question with upgrading audio

Hello community,

I am considering upgrading my audio setup which currently consists of on-board audio with a pair of Koss KSC75s. I will primarily want to upgrade to something that is gaming>music oriented (although I am somewhat of an audiophile, as I have good sensitive hearing)
)

I have 2 choices with my $150 budget:

1. Get a good soundcard and use my KSC 75s with them.

2. Get a good headset and use my on-board audio with it.


Additionally, my mic is giving off background noise, will it be fixed if I change the mic or if I get a soundcard?



Thank You!