Ati Visiontec Radeon x1550 PCI(not PCIe) with Linux?

Hello i have Ubuntu 9.04 and im trying to install the driver for my ati x1550 graphics card. I have looked through online guides and i cant seem to get it to work correctly. When i goto system/admin/hardware drivers it says no proprietary drivers are in use on this system. This is a fresh copy install of linux and i need to find a noob friendly guide on installing this driver could anyone help? Thank you.