I just read again, you want 27", the only reasonable resolution is 1440p because 1080p is just damn ugly at that size.
Also, even if you oc, b450 is more than enough -
https://docs.google.com/spreadsheet...IVNyMatydkpFA/htmlview?sle=true#gid=611478281
Lastly, your current setup should have exceeded 2k.
CPU+MB: Ryzen 7 3700x + MSI B450 Tomahawk Max @ TradePac - $627
Price difference from oversea is basically no difference. You give up local warranty on mb for oversea mb for zero cost saving, not worth it. Just get locally.
Also important to note that the performance difference against Ryzen 5 3600 is minimum at 1440p. At best you gain 8% difference for some games but majority of the games you won't see a difference. You can cut down this to 3600 to open some budget for your extra hdd.
CPU Cooler: CM Hyper 212x @ Dynacore - $51
Thermal Paste: GD900 @ Aliexpress - $5
Cheap and perform same as MX-4. I am unsure of its longevity, might need to replace it every year but it is dirt cheap.
Ram: G.SKILL Ripjaws V Series F4-3600C16D-16GVKC 2*8gb 3600mhz CL16 @ Newegg - $147
Nowadays, 12gb ram is all you need for optimal gaming so 16gb is more than enough. Ram speed matters for AMD Ryzen and 3600mhz CL16 is considered the sweet price performance spot.
PSU: Cosair RM 650w @ TradePac - $135
Full modular Gold rated. Make sure it is the 10 years warranty version, there might be still 5 years warranty version in market. Pretty much the most value for money psu on market now. Same as mb, oversea psu cost saving isn't much, only a few dollar difference and you lose local warranty support.
Nvme SSD: Adata XPG SX8200 Pro 1TB @ TradePac - $243
You missed that period which cheap SSD nvme was abundance. Now all the price go up and thus, it is cheaper by a few dollar to get locally and has local warranty support.
GPU: PowerColor Red Devil RX 5700 XT @ Dynacore - $675
Oversea gpu saving is only like $10ish? You give up local warranty for 10ish saving, not worth it. Again, you already missed that period where cheap components were abundance.
https://www.youtube.com/watch?v=1uynVO4ZXl0
Casing: Personal preference but recommend looking for a spacious good airflow.
All in all - $2000.
I don't see how you can squeeze a hdd without going across 2000. Don't forget you might also need buy one extra case fan.