Red dots and cpu fan speed

to make a long story as short as i can, i have a couple of issues with my computer (i've had more than a few in the last year, starting to get on my nerves)

first is red dots on my screen. i did'nt have them, i unhooked my tv to move it, hooked it back up, and started getting these red dots all over my screen. they're not ALL over, mostly on black areas or other dark areas, and very noticable if it's a moving picture. it's not the tv (PS3 is fine), and whats odd is say i watch a movie with the black bars on top and bottom, no dots on that. from reading other forums it would seem its the GPU (radeon 4850), but literally, it worked fine, i unplugged it, plugged it back in, now dots, so... i don't know

second problem is my cpu fan speed. my motherboard went, i had a buddy replace it for me ( N68c-gs fx). i trust him, it works now, but the cpu fan i SOOOOO loud. it ran "normally" before, changed the mobo, and now it's just intolerably loud. can't sit to enjoy a movie and have to blast music kinda loud. it runs average at 4500 rpm. i read on forums that 3000 is a lot, so... i have OC tuner from the mobo, it seems to do nothing. i can manipulate fan speed and target cpu temp, put click GO and nothing happens. i downloaded that speedfan program. i can change the GPU speed, but the cpu does nothing. i even watched a video on you tube thinkin there might be another way of doing it besides changing %'s (even though it worked for the GPU), and there was another way, but THAT did'nt work either. i'm not confident enough to mess with voltages. i read on another forum it could be wiring, and i did notice one pin on the mobo where the cpu fan plugs in is'nt covered, so again, i don't know.

specs are unimpressive :

athlon 64 x2 @6000
asrock n68c-gs fx mobo
450 w PSU,
4 gigs of ? ram
radeon 4850
tons of HDD

any help would be appreciated. i don't see my friend who replaced the mobo often, and he's helped me a lot so i'd rather not bug him any more. thanks in advance.