Display problem with GF 7300GT after changing MoBo

I upgraded from Asus K8N4-e SE/ Sempron 2800+ to GB P35-DS3/ E2180. The VC remained the same - GF 7300GT. Before changing the MB/CPU i have clocked the video card from 500 core/700 ram (stock values) to 660 core/720 ram with the stock cooler, using RivaTuner. It was running on 58* not loaded to 76-80* loaded, depending on the application i was running (game, 3dMark, etc.)
Now, after i changed the MB/CPU i have the following problem: on the screen appeared some kind of ... lines or stripes, call them *** u want, like if i putted my monitor on 60Hz or lower, but its on 85 now, like allways and the lines stay. They are not artifacts, more like power fluctuations but its not from the power supply, cause my new ram and cpu use less power than my old (checked the tech specs). Thats on stock core/ram freqencies. I've tried several versions of forceware, i reinstalled windows but the problem stays. Locked the PCI-E freq to 100 in the bios. I am now with FW 163.71 and on stock core freqencies (500), cause when i try to overclock the core of the card the computer freezes when i start a game and it goes to "performance 3d" mode. No problems with clocking the ram (720 now, 700 default). Can somone that had the same problem help me fix it? is it the video, or maybe the MB? Both still have warranty so its not a prob to replace the deffective part, i just want to know whichone is it.

I'd go over to the Gigabyte website and make sure you have the most up to date bios revision available for your motherboard before doing anything else

Its also a possibility you PSU may not be providing enough power to what hardware your running.

Usually when Nvidia cards start making weird lines or artifacts of any kind, then the GPU or its associated memory got cooked.

A GF7300 isnt exactly something I'd push beyond stock clocks anyway, as it was a low end series 7000 card!

To be honest i also thought it might be power insufficiency problem, but then i checked the power specs on the new components, and the resul was that my new CPU and RAM use less power than before, when i had no problems with the VGA. Whatever, the card still has warranty, so tomorrow ima take it to the vendor and see if he can replace it, if not - 100$ on the garbage :P BTW never gonna buy an "Inno3d" card again - poor cooling, poor bundle.