Question No Video / Keeps Restarting

[moizalamgta6]

Hi,i have this issue with my pc it wont start has no video and keeps shutting down and restarting my pc was working fine like 2 weeks ago and yesterday i pressed the power button and there was no display on screen but after 5-7 seconds the pc was off and started again and it keeps doing this my motherboard is GA-EP35-DS3l rev.1 i tried new processor or even new ram and even the graphics card is fine but the pc wont turn on
SPECS:
Motherboard - EP35-DS3L
Ram - 5GB ddr2
GPU - HD6670
CPU - Core 2 quad Q6600 2.4ghz

i have checked all cables and everything is in place,
and also the PHASE LED Lights near ram are all on.
i've been using this PC for 5 months now everything is new here.

 

[Lutfij]

WHen posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list them like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:

Include the age of your PSU.

In all likelihood, they aren't new, rather second hand parts.

 

[moizalamgta6]

CPU: Core 2 Quad Q6600 2.4ghz
Motherboard: Gigabyte EP35-DS3L
Ram: 5GB DDR2
SSD/HDD: 500gb
GPU: AMD HD6670
PSU: 300watts
Chassis: GZ-X7
OS: Windows 7 x64bit
Everything is freshly and newly installed except the processor