Some Question Unanswered

1. Newly built computer won't turn on?

You should not have to change jumpers around. Check the motherboard manual and make sure all the jumpers are at default. Remove the motherboard C-MOS battery for 5 mins then re fit.

Make sure you have plugged in the yellow and black aux 12v 4 pin connector near the cpu from the psu.
Make sure that the CPU you are using will work with the motherboard, check the CPU compatibility chart on the motherboard vendors website, you may need to have a certain BIOS revision for the CPU to work.
Make sure that the mouse and keyboard are in the correct sockets in ps2 type.

2. Trend Chipaway Virus during boot up?

Both indicate that it is the on-board anti virus protection that is not very accurate.

I would go into BIOS and disable it to be able to start the computer and then do a virus scan with the software that is used and also an on-line scan such as Trend Micro HouseCall .http://housecall.trendmicro.com/uk/

If those two will find nothing, then the on-board virus protection would stay disabled if it was my computer.