Okay, your subject line asks one question, and then your post seems to
ramble about another.
Wanting to upgrade from my P4T-E/P IV 2.0/1 GIG RDRAM...
I understand you have a P4T, so you own a ASUS board.
Would someone
tell me the difference pls...gives me a headache trying to figure out
the difference and which to buy?
Your looking at the P4C800 vs the -E? the P4c800-e gives you some RAID
options, firewire and onboard 6 channel sound.
The non-E release uses a 3com network controller, thereby ignoring one of
the benefits of the i875p chipset and CSA,
the -E version uses a intel gigabit controller w/csa If its a choice between
the original P4C800 and the -E, go for the -E by far.
Over clocking is not an issue...just reliability,
Well, luckily with ASUS boards, you get BOTH

I have a P4C 3.0 running a
flat stock and it flies, who needs to overclock when its already this fast.
I couldnt push more than 15% without my RAM dropping out of Dual Channel tho
(not bad for kingston pc3200, not valueram tho)
But at that 15% (3.45Ghz) it was still stable, just heat climbed to the 60's
under load after running benchmarks for a bit, so I stepped back to default
and been happy since.
and , god forbid, is the Gigabyte GA-8KNXP a better buy
for use with a PIV 3.2?
Then lastly, you ask in a ASUS newsgroup if a Gigabyte board would be a
better buy.
Heheh, thats asking for trouble from some people

(not me tho)
For a comparison of the two boards, you may have to search around some
hardware review sites and see what they say.
You also dont mention if you mean a P4C 3.2, P4EE 3.2 or P4E 3.2 (the
differences which can be found at intel below)
http://indigo.intel.com/compare_cpu/showchart.aspx?mmID=857353,857995,852351
You'll have to check Gigabyte for their support of Prescott CPU's or EE
edition.