How to find chipset and speed

I am trying to find out if I can use a EXTERNAL sony DRU-500AX DVDRW case and Install a new Internal DVD Burner , seems from all the Info I have found that it will fit but I was told the Speed may not be so fast as Older CHIPSET
does anyone Know what chipset is in the EXTERNAL sony DRU-500AX or how do I find out ( i have the Unit open and Lots letters numbers )
and does anyone Know if replaceing the Drive inside the Box is a Good idea or better to Buy a New EXTERNAL DVD burner ( But much cheaper to replace a Internal inside old Case )

thanks for Help Guys