Try this:
1. Go to C:\Program Files\EA Sports\Fifa 09\data\cmn
2. If you play with the fifa 09 graphics levels set to high, open "cfg_pc_h.ini", if you play with the fifa 09 graphics levels set to medium open "cfg_pc_m.ini", and if you play with the fifa 09 graphics levels set to low, open "cfg_pc_l.ini"
3. Go to the line that reads "RENDER_RATE_MODE = 7" and change it to "RENDER_RATE_MODE = 3"
4. Save the file.
5. Open fifa 09, play a match and check to see if the stuttering has gone.
I doubt the stuttering will be caused by your lack of RAM, I only have 1GB and I run fifa 09 on high with no stuttering

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