Boot Up Issues - Must Hit Reset For PC To Boot

This is a new system, about 2 months old. PC hardware below.

Windows 7 64bit build 7100
P6T mobo
Core i7 920
6 gigs ddr3
1tb hd
1200 watt psu
Geforce 9800gtx+ (soon to be replace with radeon 5870)

The issue: Sometimes when starting the pc from beeing off, nothing will come up on the screen. No POST, or anything from hd, nothing comes up at all.. In those cases I've learned if I hit the reset button, the pc will then boot normally. This happens about 80% of the time. The other 20% the pc boots fine. I can also restart the pc from windows 100% of the time.

This all started about a week ago after I had issues with getting online. My other two computers had internet access, but this one did not. I tried several ways to fix it including reinstalling network drivers, windows restore. Then I found the issue, my gigabit switch needed to be restarted. I unplugged and replugged its power and I got my internet back. The next morning I went to start the pc and nothing came up. So something happened the day before to cause this problem.

Things I have checked/done: Made sure all components are well seated. I have also reset the bios.

Please go through the checklist below as if you were checking someone else's work.

Half or more of "New Build Won't Boot" problems are resolved there, and it saves you a lot of message turnaround time versus our walking you through it here.

http://www.tomshardware.co.uk/foru [...] _13_0.html