Why? Because its discontinued. It uses the same chips as do all the other DDR500 2-2-2-5 RAM uses; Winbond UTT (it stands for UnTesTed). Winbond doesnt make these chips anymore. The closest you are going to get is Team Xtreme PC4000 UTT. They have them http://www.tankguys.biz/team-xtreem-...4f8b7963cf837f
Just to tell you, they are on backorder ATM. But they (an in tankguys) are super. They are very good with customer service, they also have a forum. Ive talked with the starter of the company, and hes a great guy. Dont be afraid because you havent heard of them.