Overclocking variables

[Antoneo]

I've gotten my Sempron 64 Palermo 2800+ to 2400MHz @1.55v (300x8) Prime95 stable for ten hours with load temps at 51C and idle temps at 38C (as reported by speedfan). I do not have a case with good airflow as I do not run any case fans so ambient temps do reach 40C.

Sempron 64 2800+ with stock HS+Fan and Arctic Silver
DFI NF3 250GB
Corsair Value Select 2x512MB PC3200 RAM
FSP 300 Watt PSU with 18A on the +12 rail
ATI 9800pro
200GB Seagate 7200.7 HD


My question is which variables have the greatest chance of affect overclocking (to stable)?
CPU "quality"
Cooling + temperatures
Motherboard BIOS version
Power supplied to the system

Did I leave any out? How does one know which component is limiting an overclock? I'm trying to figure out which component I need to upgrade or add in to work towards a better overclock. I'm currently considering buying quiet case fans and perhaps a better heatsink, but would it all be in vain?

Is testing with different hardware sets the only way to verify that suspicion? I'm not entirely new to the overclocking scene, but I'm not experienced either. If you could give me some advice that'd be great.

I have to order a another set of s754 hardware anyway so I'll be researching and hopefully fiddling with that computer soon as well.

 

[kleinwl]

Absolutely #1 ---- CPU quality!

In decending order:
Mothboard quality (along with BIOS)
Cooling quality
PSU quality
RAM quality

If you are seeing large voltage fluxuation a better PSU may be in order
If you are seeing low FSB capability (with DDR100 & CPU multi @5) a new motherboard is in order
High temps? Better cooling if possible (ie if XP-120 isn't getting it done...)
50C is fairly high for full load...throw in a fan or two and see how much improvement you can get... typically 10C is about 50 to 100MHz more overclock
Ram is almost always "good enough" as long as it is kept at it's rated speed