Vanity Mining Error?

Vanity Mining Error?: Well after getting a new graphics card (7770) I can mine bitcoins at around 180-120Mhash/s...

Well after getting a new graphics card (7770) I can mine bitcoins at around 180-120Mhash/s Depending if I run it at full power or not. Now I thought I would try and mine myself an address using it but the miner just seems to not work. Using Vanitygen (Linked below) oclvanitygen I set it off mining with reports of it mining at around 4MKeys/s but nothing was showing up after 5 mins worth of time(I tried a simple prefix of 1r). I then tried using just vanitygen64 and in seconds it found an address. Does anyone know why? https://bitcointalk.org/index.php?topic=25804.0

Full article: http://bitcoin.stackexchange.com/questions/5947/vanity-mi...