GTX 260 cause of reboot?

Have you checked the event viewer to see why it was restarting?

Well it the event viewer says kernel power for all the times it has rebooted. i also have a ups connected would that cause anything?

Its possible but unlikely, I would say it was your PSU not having enough power under load. Does your PSU have PCIE pins on it or are you using the molex adapter?

What kind of PSU do you have?

no molex adapter it has the pci connectors

power supply is a huntkey 600w model hk600-53ap

Its possible that the connectors are not supplying enough Wattage to your card or its trying to go out on you. What is the brand and model of your PSU so I can check its specs to properly diagnose your issue?

huntkey HK 600-53AP serial number 9g 002473

ac input 230v 50hz 5A

Sorry it took me so long I am trying to do to many posts at once. I checked the specs on it at the manufacturers site and it looks to me that it should be able to handle your card but I cant say for certainty because I couldnt find anything solid on the power output of the PCIE connectors, nor did they even mention the PCIE connectors. Ill keep researching though before I give my final opinion on the PSU.

thanks will keep checking here to see what could be the cause.

Okay this is the only site I have found that has stated its complete specs:

http://www.universecomputers.com/psus.php

They are saying that it only has 1 PCIE connector a 6+2 pin, My guess would be that it does not have enough power on that rail to provide enough power for a 260GTX as it needs 2-6 pin connectors. Do you have power going to both power connectors on the card?

will reconnecting everything inside help?

i had that problem, it turned out to be the temps. keep an eye on that. but since the event viewer does say power, it may be ur PSU. it should bee able to support your card easily. the best diagnostic measure is to check ur components on a friends rig.

wierd thing is that it has a 6 pin + 2 pin and one other 6 pin. dont have a spare rig or a mates pc with high end parts. i do have a molex adapter. Could using the 6 pin plus 2 pin power connector and a molex adapter make it work proper or is that asking for a miracle. will check temps to see how high it is running at cos gpu runs quiet. will check both and check otherwise back to the store we go.
Oh and i do have two power connectors goin to graphics card.

will upload pic of power supply and connectors.