building a new pc - no display, no beeps

"Things to check;

Make sure all the power connectors are connected and secure
If you can, try another monitor or a dedicated graphics card

The problem could be with CPU or motherboard. Did you use thermal paste when seating the heatsink?"

This probably does not apply to you but I recently had the same effects with an Intel motherboard. It turned out that I plugged a 4pin VGA power connector into the CPU power socket (the power supply had two 4pin conectors and silly me did not read the labels).

"According to Crucial.com, your motherboard supports:

240-pin DDR3 DIMM Banking: 4 (2 banks of 2)
Chipset: AMD 785G
DDR3 SDRAM Frequencies: PC3-8500, PC3-10600, PC3-12800 and PC3-14400
Error Detection Support: Non-ECC only
Graphics Support: PCI Express x16
Max Component Density: 2048
Max Unbuffered DDR3 SDRAM: 16384MB
Module Types Supported: Unbuffered only
Supported DRAM Types: DDR3 SDRAM only

Please make sure of the following:

The RAM is either PC3-8500, PC3-10600, PC3-12800 or PC3-14400
All of your RAM is the SAME speed and size
Your RAM is Unbuffered/Non-ECC (if it is classified as Server memory, ECC memory, or Buffered memory, you have RAM that will not work in your computer.)

More information:

http://www.crucial.com/store/listparts.aspx?model=GA-MA785GMT-UD2H"

"You might check power

instead of the std 4pin 12v cpu pwr you need the adapter for the 4pin to become an 8pin 12v cpu plug/"