Weight Vs. Pump

[polkatolka]

I am a hard gainer, with arms like noodles. What I want to know is, who thinks lifting HEAVY 4-5 reps is most likely to spark growth, and who thinks its more important to focus on the pump and not neccisarly the wieght. Now I now that Ronnie Coleman says its both, and I agree, but the only way for me to get an incredable pump is by doing a great many reps with a wieght thats easy to move around, but I've never had much growth with this. And what about all those power-lifters, those world's strogest men from TV, they're all huge and they just lift extremely heavy stuff, now you cant tell me that they started with little pussy weights with high reps to get huge, you gotta lift heavy! I think,? also if I do lift heavy whats a good rep #? for arms? for back? for legs? squats? will 4-5 do anything or do I have to go up to 8? i feel like if I stay low I might feel it too much in my joints and not my muscles.
I know I am young and I have alot of time to figure it all out, but I also see 19 year olds with HUGE arms and I wonder, how the hell? thy're not all from genetics

Thanks for the help everybody!
will post pictures soon

[DBee]

ive been on rippetoes using 3x5 for compounds and have been gaining

btw im not too concerned with the whole rep scheme i train for strength eat for size, if you want big arms eat like you want big arms and go heavy on those compounds!

heres a workout chart i made for a rippetoe variation

http://www.clanrabid.org/rabid/voidobot/wp.jpg