A new laptop is probably out of my reach for at least another year so I wanna upgrade my RAM to get a little better performance since I multitask a lot. I have an HP Pavilion dv4000 with 1 GB of RAM (2 512 sticks). I found a couple brands that were around $150 per 1 GB stick and then others that were around $60 per 1 GB stick. Why are these prices so different? Are the cheaper brands really more crappy?