Can anyone tell me what the difference will be, and more imortantly,
how MUCH a difference I will ACTUALLY notice, between having 667mhz RAM or 800mhz?
thanks
The difference you see will depend a lot on what you are doing with your computer. If you're just browsing the web, sending emails, watching videos and listening to music, you probably wouldn't notice a difference.
On the other hand, if you are doing gaming or video editing / converting, you very well could see a difference. A lot of times, however, the amount of RAM is more important than that upgraded speed. For example, if you only have like 512 MB of ram upgrading to 2 gigs of 667mhz ram is going to be much better than just swapping out for 512 MB of 800mhz ram.
If you're looking to buy new ram right now I would recommend using the 800mhz. It is worth it if you are trying to do anything that uses a bit of RAM.