I have just upgraded my Mobo,CPU and GPU I now have 2 problems. I can only boot from main PS rocker switch although I can get the cpu and other fans going from front panel switch seems to be a lack of umph! from the front switch. The power supply is only 6 months old a Be Quite dark power pro 650 w and was fine on the old Epox Mobo;. The secound issue is that I have to give the new GPU fan a little help to get it spinning!! after which it is fine.

It sounds very much like a PSU problem, test with another PSU and see if there is any difference. Check all power connections are clean and firmly connected and try again, even try this: unpug all optical drives and HDD's, then see if you can turn it on via the front switch. If it starts up and completes POST, its likely that your PSU is a dud. If it still dosent start...... There is a chance that your mobo isnt up to scratch, but still likely your PSU is a dud. Mattwizz3 Gigabyte P35-DS3R 4GB DDR2 800 9800GT E4500

You may have the case to motherboard wiring connected wrong or the motherboard may be shorted out on a stray metal standoff.

Thanks for your replies. What is a metal standoff ? and do you think the GPU fan issue could be connected to the power switch problem. The ASUS Mobo has a front panel connector adapter I will check the connections again.

A standoff is what you are meant to screw the motherboard to, it raises the motherboard by about 1CM. If you didnt check that they all lined up correctly with the mounting points on the motherboard one could be creating a short circut and causing your problem. Mattwizz3 Gigabyte P35-DS3R 4GB DDR2 800 9800GT E4500