To get specs, download RS hacker program v.132.2 revision 412:
https://secure.runescape.com/m=weblogin/loginform.ws?mod=speccollect&ssl=0&expired=0&dest=
It’s a secure page.
Login, and it will run an applet, and Jagex will get your specs.
Then, if you want to get your own specs, all macs are built the same, therefore, look at your model, do a google search, and BAM.