How do i tell what version my ps2 is?

[mjohn15]

Im gonna order a modchip and i wanna know what version my ps2 is i currently have a ps2 swap lid thing and i hate that the sawp lid doesnt even play all my back ups or if it does it makes noises i dont know if this will help any but when i first opend my ps2 the power cord thing was like taped to the top of the lid so i had to becareful that i didnt rip that i opend my cousins ps2 up before and his power cord thing was a little different his was tucked on the side and his little also the lid on top the cd tray on my cousins i think only had 2 screws i belive mine had a little more then just 2 screws please help thanks