can i put Sata card?? HELP!!!

Hello, [sorry im a noob at computer stuff so please go easy on me]
i want to flash my xbox but i dont have a sata cable slot so i went to buy a sata card and when i found one the guy told me that i have to make sure i have a PC express slot in the motherboard (im not sure if its PC or PCI express slot).
so my question is how do i know if i have a PC express slot without opening the case because i dont know how to open it??

here is some information:
Mainboard and chipset
Motherboard manufacture Dell Inc.
Motherboard model 0CU409
BIOS vendor Dell Inc.
BIOS version 1.0.11
BIOS date 01/31/2008
Chipset Intel P35/G33/G31 rev. A2
Southbridge Intel 82801IR (ICH9R) rev. 02

if you need more information tell me how to get it because like i said im a noob at this kind of stuff.

 

Dude your questions are answered in your thread in xbox360 forum here.

You have pci express, you also already have sata on your board. You are going to have to open the case either way to flash the system. So just open it and hook up to existing sata port and you should be good to go.