Weird 2100 B

Ok, just got this chip yesterday. I had no expectations really so I was happy to see it run at 13x166 at default Vcore. After that I lowered vcore to 1.55v and ran a stability test: Endless loop in 3Dmark2001 for 10 hours(then I ended it).

Now Ive been trying to achive some more..:
12x200: Hangs at BIOS screen, CMOS clear
11x200: " " " " "
13x180: Windows cant load, err msg
12,5x180: " " " "
12,5x175: Restart during windows load

I tried Vcore 1.6, 1.625, 1.65 and 1.675 volts. I used relaxed mem settings at actual FSB.

I think its weird that it wont work at all at 175 Mhz FSB when it works absolutley flawlessly att 166 Mhz undervolted. Dont u?? Or am I being a chicken when it comes to Vcore?

System:
XP2100 AIUCB 0241 brown
Epox nforce2 mobo
2 x Twinmos Pc3200 256Mb(Winbond)
Gigabyte Radeon 9700pro
Alpha pal8045
Enermax 550 watt psu

my tbred does the same thing
if you're man enough to do it, crank up that voltage.
i went up to 1.85v with only a 3c degree difference (using water cooling) so if you have good cooling, it should be a problem, but then again, go up slowly just incase...

Yes you are being a chicken

It sounds like the default Vcore is 1.6 on that chip (correct me if I'm wrong)

Many people go up to 2.0v on the T-breds, but I wouldn't recommend that unless you have some serious cooling.

You should be able to get to 1.85 with GOOD air-cooling. That, even 1.75 should give you a stable overclock at those speeds. There are many pulling 2400mhz out of these chips on air.

For reference, on my 1700+ T-bred A, the default Vcore is 1.5. I've run 1.85v with no problems, but had to back down to 1.75 due to excessive heat. I'm getting 180x10 at this voltage.

Mine too is about the same. At 1.7v I can only go to 174 or so. Unfortunately my board only goes to 1.7v or I would definitely be upping it much higher.