It is actually very simple. You can handle yourself. Take the classic list of equipment.
- Video card
- Hard drive
Go to the website of the manufacturer of the specific hardware characteristics power state.
- GIGABYTE Z390 UD, 1151v2 LGA, Intel Z390, ATX, Ret
- INTEL Core i5 9600K, LGA 1151v2, OEM - up to 200 W
- DEEPCOOL deepcool gammaxx 300 FURY, 92мм, Ret - 1 W
- SAPPHIRE AMD Radeon RX 580 , 11265-05-20G PULSE RX 580 OC 8G, 8Gb, GDDR5, OC, Ret - up to 225 watts
- WD Blue WD40EZRZ, 4TB, HDD, SATA III, 3.5" - 5 W
- 860 SAMSUNG EVO MZ-76E500BW 500GB, 2.5", SATA III - 4 watts
- KINGSTON HyperX Predator HX430C15PB3K2/16 DDR4 - 3000 2x 8Gb, DIMM, Ret
Where not specified power consumption is usually it is relatively low. MB, RAM is not critical. So, consider: 200 + 1 +225 + 5 + 4 = 435 W. Do not forget that there are still peripherals. We will add 25%. 543 watts. 543 W
is a critical limit on energy consumption. It is also necessary to consider that the power supply has an energy-efficiency and efficiency. Let you have a good PSU that gives not less than 90% efficiency. Total, this system requires at least 600W (these are the numbers that are written on the box of the PSU). Plus to have a stock very desirable, given that the Chinese could easily lie about the watts and efficiency. And that 15 percent is the bare minimum. Already BP and 700 watts (these are the figures that appear on the box) is the norm with the stock.
Here is an approximate counting algorithm.