The only part of that screenshot pertaining to system memory is the 8GB part.
The top is VRAM. GDDR5 is actually quad pumped as opposed to double pumped like desktop DDR. Regular DDR ( double data rate ) transmits information on the rising and falling edges of the clock cycle. GDDR ( graphics double data rate ) transmits 2 pieces of information on both the rising and falling edges of each clock cycle for a total of 4 per cycle.
Here's where it gets confusing.
Some programs continue to read GDDR clocks at the base which in that case is 1750mhz. Some double it since it's sending 2 pieces of info per cycle so that's what you're seeing in that screen shot at 3500mhz. Some read the effective speed which in this case is 7000mhz.
So, TL;DR. That's a screen shot of a likely GTX 970, a CPU that's badly overheating and the computer has 8GB of RAM. Anything else he's either lying or clueless.
The Corsair Vengeance 2x8 CL14 3000 MHz RAM is marked with lpx option, that's what got me confused. Aren't lpx rams are pushable to higher limits ?
LPX means low profile. That's all.