I am new to pc building and upgrading and have hit a snafu. I have a emachines T6520. The only thing in it that is original is the motherboard/cpu and the cd drives. i wanted to upgrade from my onboard video to something better to get the load of my mobo. I am trying to install a saphire ATI Raedon HD3450. Notthing to powerful because i am not a super gamer. When i install the card it makes my computer slower than a old man getting out of a bath tub. it takes almost a half an hour for my pc to fully load. I have 2 gb of ram and prior to upgrading the card installed a 550w psu. I disabled the onboard graphics and configed the BIOS how emachine support told me to. still the pc is so slow it is useless. when i have the card in with the monitor pluged in to it, my resolutions is very low so i know it is not taking it. i installed the ATI drivers prior slotting the card. my mother board is a MS-7145 RS480 754P K8 IXP400. Please help, got my new video card in a box on a shelf doing nothing.