I have a cooler master rs 400 psar j3 400w psu with dual 12v rails with 17amp on each of them
and here are my pc specs
intel core 2 duo e7500 @ 2.93ghz
ram-2gb ddr2 800mhz
hdd - 320 gb 7200 rpm
gpu - sapphire radeon hd 6670
mobo - asus p5kpl am in
and please explain me what does dual 12v rails mean because i think 17amp on a single 12v rail is very low but dual rail is giving me some hope .
Your psu is fine for that low end graphics card, the only case where you would need a higher amperage on the 12v rail's is if you where using a mid to high end graphics card that requires 2 6-8 pin periphrial connectors.
Ok let's assume that its not the best psu but can it handle my pc for 1 or 2 years because i'm not thinking about any upgrading or overclocking i will upgrade my whole system after 1 or 2 years so will my psu be enough for 2 years as i also has warranty of 2 years .