Would i need a sound card?

I currently have the sennhesier PC350 SE headset and its 150 Ω so it should need a sound card my budget is around 100-150$

Sound is normally more software and driver based than hardware nowadays. Most decent mobos come with good sound built-in as well. If you really want anything, an amp for your higher quality headsets, otherwise I really wouldn't worry too much.

Telling us your current build, or pc model, would help in our suggestions.

Operating System: Windows 8.1 Single Language 64-bit (6.3, Build 9600) (9600.winblue_r8.150127-1500)
Language: English (Regional Setting: English)
System Manufacturer: MSI
System Model: MS-7693
BIOS: BIOS Date: 10/18/12 10:16:30 Ver: 04.06.04
Processor: AMD FX(tm)-8350 Eight-Core Processor (8 CPUs), ~4.0GHz
Memory: 16384MB RAM
Card name: AMD Radeon HD 7800 Series

Looks like a sound card with an amp would be beneficial.

Perhaps the Asus xonar DG (if you want to go cheap), or the Soundblaster Z should be enough for what you need. Could find used sbz's on ebay for a decent price as well.

When adding an internal sound card to a PC, it's best to disable the motherboard's on-board audio, in the BIOS.

ah ok thank you for the help :D

Tek Syndicate actually made a couple of videos about this as you can see here and here
I really advise you to check it out because you can learn some things
But to get to the point: besides the internal sound card there are some external options you can look around to power those headphones and that will get you a better quality most of the times, but some times they may get a little off of your price range, but that's up to you. Nothing like a quick research
Hope i helped