Strange 1700+ behavior - help?

[IntelConvert]

I am building a budget system for a friend. Here are some brief specs:

1700+ AIRGA T-Bred A, default 1.5V
Shuttle AK35 GT2
1 x 512 MB Crucial DDR 2700

He would like to at least know the highest stable overclock he can expect. I had high hopes when I saw the stepping, and while I have gotten a decent jump from it, I'm seeing behavior out of this CPU I just haven't seen before.

It runs stable at (about) 1667, either at 12.5x133 or 10x166, at a mere 1.55V. However, no matter how much more voltage I pump through it (at least up to 1.8), it will not even post if I go to 10.5x166 - or even 10x167. I understand that all CPUs have a limit, but this sharp cutoff just doesn't "feel" right.

Any thoughts or suggestions?

===========================

Let me simplify. I have a T-Bred (A), 1700+ on an AK35 GT2 (KT333) that will post happily up to about 1700 Mhz with only 1.55V. However, it will not even post at any higher settings, even after raising VCore to 1.75V. Does this simply mean I got unlucky with this core?

[AllGamer]

it depends if it's a Tbred or Palomino, and if lucky Barton :p

:t

[2penguins]

Was it really stable at those settings?

How did you determine it was stable?

[cyber_gubat]

i think you lose power..... if your using a 300w psu then it may come up short.....:p

[AllGamer]

Originally posted by 2penguins
Was it really stable at those settings?

How did you determine it was stable?

run Bench Marks softwares like
3D Marks 2001 SE or 3D Marks 2003

:t

[2penguins]

3d mark will not tell you if your cpu is producing errors.

The best tool for that is Prime95.
http://www.mersenne.org/freesoft.htm

Run it for 24 hours or at least 6 hours to get a good result.