Quote (NatureNames @ Aug 7 2019 04:06am)
CPU Cooler:
I'd get a NH-D15 instead of NH-D15S. Reason being is the D15 comes with two fans while the D15S only comes with 1 fan. The D15S has essentially the same heat sink but the heat plate has been shifted off center to allow space for the GPU on X99 motherboards or other boards that have the PCI slot too close to the CPU socket. If you do use a 9900k this shouldn't be a problem. I use a D15 myself on the Z390 chipset. If you're going to overclock you definitely want 2 fans on the heat sink. The i9 is a hot cookie.
Power Supply:
I'd go for a 850W, if not more. While 750W might be enough it may be cutting it close depending what else is connected to the machine. The 9900k can use 425W alone when overclocked, so keep that in mind. (Intel says it's a 95W part but that's only true when it's running at 3.6 GHz)
HDD:
I would go for a higher quality HDD, but It might depend on how much you value your data. The Seagate Barracuda only comes with a 2 year warranty, which is rather low in the industry. A Western Digital Black comes with a 5 year warranty and is built to last longer, but it comes at a higher price. Western Digital Blue comes with a 3 year warranty. I know most people are loyal to one brand of HDD and if they ever had a drive fail they exile that company for eternity. Personally I've never had a WD drive fail on me in 20 years so I'm a loyal customer.
SSD:
I think the Samsung 970 EVO you picked is a fine choice. Samsung has a very low rate of failure and I like the Samsung Magician software. 3400/2300 MS/s (read/write) isn't the fastest M.2 drive out there but it's pretty damn fast. Most of the time a SSD won't even reach those speeds under real-world gaming / Win10 use due to software-engine bottlenecks. About the only time you see max speed is in a synthetic benchmark or perhaps in some video edit workloads (I have not tested this).
Also I don't feel comfortable buying a brand like ADATA in order to save $30 and gain +100 Mb/s that I'll never see; not when 10% of their user reviews say it came dead upon arrival or failed within 30 days. I'm sure some people will disagree with me on this matter. But for me when it comes to storage I'll pay more money for a brand I trust.
RAM:
While I do agree DDR4-3200 makes sense because anything faster has extreme diminishing returns in games, the price of 3600MHz is almost the same as 3200MHz right now (on Amazon). If you're looking to future proof it may be worth it to spent the extra $15 and get 3600 ram. In years past, the point of diminishing returns has moved over time as cpu, gpu, and different games come out. I remember when DDR3-1600 was the peak of the curve. That sure changed in a couple years time.
Motherboard:
Just make sure it has VRM that can handle the 9900k when overclocked. There is some good YouTube videos on this subject. I can link them if you want.
Thermal Paste:
You will need some paste and there is many to choose from. I went with Thermal Grizzly Kryonaut. It's not the absolute best paste but it's one of the better ones.
Saving money:
You could save money by choosing a Gigabyte mobo, sticking with DDR4-3200 ram, and choosing a cheaper case. You could also save money by buying cheap brands of HDD and SDD or slower models, but I don't recommend being cheap on these.
850w should onlly be considered when it same price
link me 9900k using 425w