My dated pc fast enough for HTPC?

Hello!,

I was reading about xbmc and i love how smooth it works compared to those buggy media players so i wanna turn my old pc into a HTPC!
Cause this pc is dated i am wondering if i can play 1080p movies and run windows 7 with xbmc.

Specs

Q8200 (quad 2.3Ghz)
4GB DDR2 800
Ati HD 4650

I want to buy the HD 4650 cause it has a HDMI port , i won't settle for Anything les then HDMI.
I also dont mind putting in more RAM.
Also i am planning to run windows on a SSD and control de HTPC with logitec dinovo mini.

Is it worth investing money/time in system?

Thx in advance!