CPU upgrade for OC and Folding

I'm getting restless to build my new system - still collecting money for that upgrade. I want to start doing some OCing. I'm thinking about upgrading my current system to practice with before getting the A64. Gotta improve my Folding!

Current setup:
Soyo SY-K7V Dragon Plus (VIA KT266A chipset)
Athlon XP 1500+ (Palomino)
256MB Crucial PC2100 CL2.5 and 256MB Generic CL3
GF2 GTS
Seagate 7200RPM, 40GB, 2MB cache
CDRW and FDD

Candidates for upgrade:
1. <A HREF="http://www.newegg.com/app/ViewProductDesc.asp?description=19-103-401&depa=1" target="_new">Athlon M 2500+</A> for $87
2. <A HREF="http://www.newegg.com/app/ViewProductDesc.asp?description=19-103-439&depa=1" target="_new">Athlon M 2400+</A> for $95
3. <A HREF="http://www.newegg.com/app/ViewProductDesc.asp?description=19-103-436&depa=1" target="_new">Athlon M 2600+</A> for $95

Some questions about these CPUs:
1. Why is the 2400+ more expensive than the 2500+ and as expensive as the 2600+?!
2. What's the difference in the core colors? - I read something about the colors before, but can't remember
right now.
3. Which has the best stable OC potential?
4. Will my current setup work for some OC? If yes, then what is a reasonable OC expectation?
5. Will the Barton core work with my mobo? Soyo <A HREF="http://www.soyogroup.com/kb/kbdesc.php?id=16" target="_new">website</A> says that the mobo only supports Thunderbird, Pally and Duron. If I can use it, would I need to change any BIOS settings to get it to run?

Without getting any new RAM, I'm thinking this may be a waste of money ...thoughts?

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Thanks for the info. Looks like it isn't worth the money for me...just save some more for the A64.

The "training" upgrade for this one will have to be after the new build!

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Youve got to watch Wusy, he works for EPOX

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