Hi, when i run games like call of duty, the sims 2 far cry i ever so often just get a slight judder and the hardrive makes a noise. I'm assuming it's paging the hardrive for memory. My system is 2600xp, 512 2700 ram, 80gb maxtor ata133, 9800 pro. I would have though i have enough ram or do i need to make the step to 1gb?