So i had a 550W PSU In my build, I down graded to a 400Watt Because it had more connectors. since then I am not able to play games on ultra without the system crashing, I get a RED screen, I am on windows 8.1 OLD PSU : http://www.amazon.co.uk/550W-Gold-Silent-Power-Supply/dp/B000KND4M8
Current PSU : https://www.google.co.uk/shopping/product/941531017487682896?q=Akasa+400watt+psu&espv=2&bav=on.2,or.r_cp.r_qf.&bvm=bv.74035653,d.ZGU,pv.xjs.s.en.jmw5uQvp5VE.O&ion=1&biw=1680&bih=925&tch=1&ech=1&psi=DfD9U6G2LumO7Qakn4DgDg.1409150990934.5&ei=H_D9U-aYIqi47AaViIGYAQ&ved=0CF4QpiswAA
Current PSU : https://www.google.co.uk/shopping/product/941531017487682896?q=Akasa+400watt+psu&espv=2&bav=on.2,or.r_cp.r_qf.&bvm=bv.74035653,d.ZGU,pv.xjs.s.en.jmw5uQvp5VE.O&ion=1&biw=1680&bih=925&tch=1&ech=1&psi=DfD9U6G2LumO7Qakn4DgDg.1409150990934.5&ei=H_D9U-aYIqi47AaViIGYAQ&ved=0CF4QpiswAA