You don't specify which RAM it is, this board support DDR4 2133 and DDR4 2400 only, no overclocking is possible. There is no use in buying RAM over 2400 MHz speed. Also, the B150 has 4 RAM slots so better to go with 2X4GB over 1X8GB. This way you will be able to run in dual channel mode.
Also, is there a reason that you chose the i3-6100 over the newer i3-7100? Not a big difference but the 7100 is a bit faster.
The PSU is a very low quality PSU, suitable for budget builds only so it would limit any future upgrades. One of the biggest mistakes that people make is to skimp on the PSU.
Not sure about the case. There was no price in PCPartPicker and it only came up on Amazon.co.uk so I assumed pounds as the currency.
PCPartPicker part list:
https://uk.pcpartpicker.com/list/jJDKkT
Price breakdown by merchant: https://uk.pcpartpicker.com/list/jJDKkT/by_merchant/
CPU: Intel Core i3-7100 3.9GHz Dual-Core Processor (£115.66 @ CCL Computers)
Motherboard: ASRock B250M Pro4 Micro ATX LGA1151 Motherboard (£84.92 @ BT Shop)
Memory: G.Skill Ripjaws 4 series 8GB (2 x 4GB) DDR4-2400 Memory (£59.30 @ Amazon UK)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive (£44.32 @ Amazon UK)
Video Card: EVGA GeForce GTX 1050 Ti 4GB SC GAMING ACX 2.0 Video Card (£153.93 @ Amazon UK)
Case: Aerocool VS-1 ATX Mid Tower Case (£42.88)
Power Supply: Antec EarthWatts Green 380W 80+ Bronze Certified ATX Power Supply (£43.47 @ Scan.co.uk)
Total: £544.48
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-01-25 11:42 GMT+0000