Zotac 9800 GT OC problem?

[AAAthreat]

Lo and first post here . I recently upgraded my ageing 7800 GTX to a Zotac 9800 GT and now ive had the 9800 GT for a couple of months I thought I would try and OC it. Well I was surprised when the Zotac wouldnt even get up to 700 without crashing my games (this was using Rivatuner) so I d/l ed ATI tool to check the temps and test my over clocks before trying anything ingame.

Well with ATI Tool I can overlock the card past 700 and leave it scanning for aritfacts for over an hour and its fine but when I jump into a game it will last maybe 5-10 minutes before freezing up. The temps arent going past 50c.

Core Clock 655
Memory Clock 943
Shader Clock 1637

Above is the most ive managed to get out of it before I evetually crash ingame... That was after about 2 hours of playing different games the temps didn't go past 35. The crash is mostly the same the game freezes and does nothing but I can still hear sounds ingame.

I have the latest Nvidia drivers and the latest version of Rivatuner and ATI Tool. Any help would I would be grateful.


System Spec. Below.


Windows XP pro.
Core 2 Duo 6700 Oced to 3.2 ghz
Zotac 9800 GT (latest Drivers)
Asrock Intel 945GC A2
PSU 550 Watt.
2 GiG DDR II PC 5300

 

[D13]

I am not too familiar with gpu oc'ing, but perhaps look into using the evga precision tool, I believe it has a very good reputation for oc'ing nvidia cards.

Also perhaps it is possible that the card has simply reached it's perfomance limit?

 

[AAAthreat]

Thanx mate I might look into that Evga tool, yeah you could be right about the card reaching its limits it was just I got the impression from more than 1 review that these cards were capable of good overlocks.

Those overlocks ive put in the first post are hardly any different from the default clocks, also the fact I can overclock them quite high and leave stress test programs running for over an hour yet when I play a game it will crash pretty much straight away.