problem overclocking x1950xt

[Luke2]

Hi - I have HIS x1950xt with TR HR-03 cooler http://www.newegg.com/Product/Product.asp?Item=N82E16835109134
The temps are under 70C in full load
I use ATitool 0.26 for overclocking - but everytime I try to overclock the core for example - It's very unstable having to reboot the PC after about 2 minutes running the 3DView in ATitool(fuzzy cube)...
I did set the voltages higher - as you can see in the screenshot - the VGPU is on 1.5 and the clock is set to 681 (anything above won't even let me start 3dmark06) - it'd freeze right after about 3 seconds
The memory is set to 2000(effective) and I think I should have no problem running at those speeds
http://img179.imageshack.us/img179/2841/untitledos7.png
Other people reach 700 on the core smoothly...
So I was wondering what the problem could be and the only thing I could think of is that i son't have enough juice from my PSU - Even though I have this on it also - http://www.newegg.com/product/product.asp?item=N82E16817153037
My current PSU is Enermax NoiseTaker 485W Dual 12Vrails 33Amps Total
That could be the only problem I'm thinking of - or AM I WRONG ???
Please Help

Here is rest of the rig
I got AMD 64 3700+ San Diego @ 2.6
2x1gig Corsair Valueselect DDR400
85GB 7200RPM WD HardDisk
Epox 9npa+ultra
SB-24bit Live
DVD burner

Thx for replies

[newbuilder14]

That is such a purely powerful card, why do you even need to overclock it?

I wouldn't mess with the voltages too much, either. Some cards just don't overclock well, and trying to force it to with extra power can be for better or for worse.

[Luke2]

plz admins delete this post - I decided to buy a new PSU
sorry bout it

[newbuilder14]

Not a bad idea. Thought the one you have now is good, that is probably the minimum wattage I would trust on a setup like yours - and adding overclocking just makes it too much for 485w I believe.

Now, you say you had a graphics card power supply - if you had that connected then I'm not so sure why you are having instability issues.

You may have not needed to buy a new power supply.

[Mr.Ferrari]

Very nice start and an excellent cooler. Your orginal psu is more then enough, you have no need for the thermaltake, fyi.. ;)

Now I would start out with making sure your using atleast ati tool Beta16 Pre8 (http://www.techpowerup.com/wizzard/ATITool_0.25b16pre8.exe) version.

Next make sure that your saving your voltage to your profile. You might be booting up with default voltages but same clocks.

And what drivers are you using? Make sure your either using the special version 6.10's or 7.1's!

Have you disabled the 2d/3d clock switch through Ati tool? I.E Ati Hotkey Poller & Ati Smart.

And I dont like the fuzzy cube. I play a game for 20min. to check stability between every overclock. The Cube has been inaccurate for me and has caused corruptions in my overclock.

[Luke2]

Well the thing is - that I will probably be upgrading CPU etc etc... You know how it goes with technology - so I'll just buy a new PSU and get that out of the way.
Now..- This is the PSU I'm buying http://www.newegg.com/Product/Product.asp?Item=N82E16817341002
The question is : I could still have the VGA PSU (thermaltake booster) connected to the VideoCard or I could just run it off of the new PSU - would there be any difference ? and what would be better ?
thx

edit : Mr.Ferrari : I have tried all of the above and even when playin a game thee thin craps out...