EDIT: the previous poster has some very good suggestions as well. test one component at a time. the 3 components you'll be working with: FSB, CPU, and RAM.
1: Lower your CPU multi, set the lowest RAM speed you can...and up your FSB till you find instability..adding NB voltage as needed.
2: Leave your mem setting alone, and up your multiplier till you find instability..adding voltage as you go if needed.
3: Drop your multiplier back down, and increase RAM speed or timings..adding voltage as needed.
Now you know your maxes.
4: Find something in between that works for all 3 at their fasest settings.
ibt should run with option 1 on that system, weather 32bit os or not.
what are you using for temp readings?
i've never heard of a sub 30c idle on air...
use tjmax of 100 for whatever app your using. i'd suggest real temp, or everest.
95 tjmax is what some also swear by, but will show lower load temps at the same time.
i've seen some 72c (max) readings w/ IBT and 100 tjmax.
to me, thats gettin a bit hot...granted, RARELY are you ever going to see anything near that in normal gaming/usage..
even crysis won't approach that during normal game play for hours...
IBT to me is 1st n foremost a quick and easy stability tester. if it doesn't pass 5/5, i go back to the bios.
once it passes 5/5 ibt runs, i go to orthos for the 12+ hr testing.
or start doing combos. orthos + loop 3dmark.
or, orthos small + memtest (win version)
and so on.
Also, another tip to find peak performance for a given setting...
Run some benchmarks.
I use Everests memory/cache benchmark for each setting.
I also run 3dmark 06.
This gives you a better idea of what FSB or memory speed/timing is better than another..
Hint: 3dmark likes more CPU Mhz than RAM Mhz/timing...
I use a spreadsheet and keep track of ALL of my settings, fill in every collumn each run, max temps, voltages, mhz, ratios, bench results, hours spent stability testing, passes made, blah blah blah...
and yes, this is exactly why a lot of people find over clocking a "waste of time", cuz it literally is a lot of wasted time.
theres a lot more to overclocking now days. it was so much easier in the jumper/dip switches days. LOL
coreV, fsbMHz, multiplerX...gg...
granted, then you were hunting for + ~50MHz instead of tryin to push + ~1GHz. haha