While the 6770 was not known for a light load, I missed what PSU you have as well as if you tried this with a single stick of RAM and BIOS defaults.
My specs are:
Processor: AMD FX 8320 Black Edition
Motherboard: Gigabyte 78LMT - USB3
RAM: 16Gb DDR3
GPU: MSI Radeon HD 6770 DDR5
OS: Windows 10 (updated till now)
My problem is... pc is restarting again and again after windows logo with displaying 'No Signal' initially.
Sometimes during restart loop it gives display then again 'No Signal' and sometimes it keeps restarting in the background with 'No Signal' message on screen.
I've tried using motherboard display and it didn't worked first but second time it worked.
I also tried safe mode and all but the same problem exist.
I've also checked Connections, reapplied Thermal Paste, removed the CMOS to reset it, tried BIOS settings but after few seconds it shows No Signal when display is connected to GPU.
Please help me.. do I need to change my GPU.. (it's old anyway) or is there something wrong with PSU.

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