Normal working temp for a GPU is up to 85-90°C, so you're fine. Monitor the temperature further and see where it goes, 78° is low. For a GPU, keep that in mind. You can use "hardware monitor" (just google it) to find out other temps you have there, if you have a general venting problem, you may want to check system temperature, you don't want your chipset overheating or possibly negatively affecting the CPU.
As far as overclocking goes, I wouldn't recommend OCing the GPU. But that CPU should have overclocking head room. If you haven't done any OCing before, I recommend reading some guides and try to find people who have similar systems as you. Their results can be used as a guide, but do remember that every system handles overclocking differently. Motherboard and power supply are major factors.
I assume you have a 64 bit OS there, you may want to try using memrestrict
, that can help with performance at times. How fresh is your OS installation? GTAIV can be very sensitive, a defragmentation + ccleaner + AV scan run (I recommend MBAMI) can only help. This post has been edited by mkey82 on Friday, Apr 13 2012, 08:56