First build - will it work?

[Bricatt]

Hello everyone!

I decided to buy a new PC and build it myself as it is cheaper.

I have some questions which I hope you can help me with.

Is there a significant difference between DDR3 and DDR4 memory? Is a 8 gb DDR4 better than a 16 gb DDR3?

Also, can the build use a mid tower? Don't know the difference between it and a full one. The price difference is quite considerable.

And, finishing, if there's something that could be cheapened (such as the Mainboard, power supply, fan...), please tell me!

Here's the build:

Spoiler

HV20IS09DE Intel Core I5-6600K Bx, Sockel 1151, ohne Kühler 250,99 €
HV1144IIDE Gigabyte GA-Z170-HD3P, Sockel 1151, ATX 120,99 €
HV30AP54DE Alpenföhn Brocken Eco 34,99 €
HV20KL52DE 16GB-Kit Kingston HyperX Fury, DDR4-2133, CL14-14-14 86,99 €
HV203FE5DE FRACTAL DESIGN Define R5 Black, ATX, ohne Netzteil 107,99 €
HVR630TCDE Thermaltake Berlin 630W 60,99 €
HV1035UVDE ASUS STRIX-GTX970-DC2OC-4GD5, GeForce GTX 970, 4GB GDDR5, 2x DVI, HDMI, DisplayPort 368,99 €
HV13SB71DE Seagate Barracuda 7200 1000GB, SATA 6Gb/s 50,99 €
HVXK017MDE SanDisk SSD Z400s 128GB 2,5 (SD8SBAT-128G-1122) 42,99 €
HV207GB4DE LG GH24NS bare schwarz 12,99 €
HV25TWMLDE TP-LINK TL-WN881ND Netzwerkkarte/-adapter 15,99 €

Or here with this link:
http://www.hardwareversand.de/pcconfigurator/meinpc/1383637

Thank you very much in advance!

 

[CTurbo]

Drop to an i5 6500 or 6600 and get a H170 motherboard instead. The stock cooler would be fine.
There is not a significant difference in ddr3 and ddr4 RAM.
630w is more than enough but that psu is low quality.
I recommend a psu by Seasonic, XFX, Antec, or Super Flower. 550w is all you need.
I recommend a ssd by Samsung or Crucial.