And OSes won't install it's most likely hardware but does not tell us it's RAM.
The 5700 and 6700 CPU are very old. So we can't be sure of much other than to clean up the PC, reduce any parts we can such as unplug WiFi, Ethernet, disable sound in the bios along with fresh heat sink compounds, fan checks and a current BIOS.
http://ark.intel.com/products/27251/Intel-Core2-Duo-Processor-E6700-4M-Cache-2_66-GHz-1066-MHz-FSB pegs this PC at over 10 years old.
My advice is to also inspect for BAD CAPS (see google) as you repace heatsink compounds. The PSU SHALL BE over 400Watts, single rail as well.
When I attempt to install Windows on a new hard drive in my desktop, the installation never completes. It goes so far then the monitor goes black (enters power saving mode).
I have experimented installing from my retail Windows 7 dvd, also tried installing Vista from the dvd. In each case the monitor goes black before completion, though the computer keeps running. I experimented with Linux and that installed ok.
I have just run the Windows Memory Diagnostic tool, half way through running it the monitor went black again.
Would all this point to a problem with the memory?
I am running Windows 10 Pro 64bit
Graphics card AMD Radeon HD 5700 Series
ASUS P5P43TD motherboard
Processor Intel® Core (TM)2 CPU 6700 @ 2.66GHz 2.67 GHz
Ram 4.00GB
I would much appreciate any advice.

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