Different speed memories and sizes?

Hi I Have been using 1 x 512 stick of 400 mhz memory in my computer for a bit now and been noticing its not enough.

My ex girlfriend just fried my old computer I gave her that had 2 x 256 sticks of 333 mhz ram in it.

What would be the implications of running not only 2 different speed rams but different size sticks???

Im assuming it would be just the equivilent of 1024 mb's of 333mgz ram??? Is this correct???

Also do you think it would help at all my slugish issues when the comp has been on a bit???

Would it REALLY slow down my games or apps???

Actually the more I think about it. doesnt my cpu run at 333???? So pc3200 isnt running at full speed anyways???correct???

You are correct. I would think it would be worth a try. I would also think your slow issues may be a result of temperture.