how do i know?
Please avoid spamming.
If you are using windows 10, locate your Taskbar and the search bar, type DXDIAG in the search bar. This will run the DirectX Diagnostic Tool. Take a screenshot using the PrintScrn button, paste it in Paint or any photo editing software. Then upload the image on here as a response by clicking on the "Add Image" button when replying.
I'll try my best to help you with your issue.
Ok sorry but im windows 8.1
if its on windows at all, and you've got a standard keyboard to go with it - hit the windows/brand button on said keyboard, usually between ctrl and alt on either side of the keyboard
Then hit R
Usually people will say it like "Win+R" keys. Hitting them at the same time (or holding one and then hitting the other) will bring up Window's run cmd-line - Typing dxdiag from there will give you the basic run down of your computer specs.
There's 2 pages (generally) of basic specs, the first page is nearly all basic except gfx chip/card - the second will tell you that one, along with some connective devices, sometimes. The other pages aren't generally useful in situations like this.
If win+R doesn't work for you, like Dasius was mentioning, you can simply open the start button, and then in the search bar, type dxdiag and hit enter, you don't have to way for it to actually search for dxdiag or find it in the list. - This feature should work on Most Vista+ versions of Windows... I think.. maybe one of the versions of xp had it... but maybe not.. I dunno. My memory isn't "great"