I have Hauppage HVR 1600 working wonderful under 8.10.
You already have followed wiki for the card although there is no need. because, the device is now plug and play since we have device template for the card.
Remember, you will get only digital tuner get working. for some reason we dont have analogue tuner working.
Most important, if you are using nvidia card, you need to change vmalloc=256M value in your boot/grub/menu.lst file.
please visit this thread :
http://ubuntuforums.org/showthread.php?t=1043884 Hope this helps.
Oh forgot to tell you, since you are not able to login, try taking it off the system. Boot up. from KDE desktop change your vmalloc value. shut down. throw the card in and boot up again.
Listen, dont give up. dont return, the card is great. works like a charm.