Need advice for 2 different systems with slightly different needs

[FrostNinja]

Building a pc in 2015 for gaming purposes, the following specs are my primary gaming pc and watching movies.

Intel core i5-6500 socket 1151 3.20 ghz quad core processor
Gigabyte b150m-d3h socket 1151 motherboard
Kingston hyperx fury (black) ddr4 2400mhz 8gb (4gb x 02 pcs)
Msi gtx 970 gaming 4g pci-e 4gb graphics card
Samsung 850 evo 250gb m.2 250gb solid state drive
Western digital 3.5" sata iii 1tb blue 7200 rpm 64mb cache internal hard disk drive
Seagate 2TB 2.5" FireCuda Gaming SSHD SATA 6Gb/s Flash Accelerated (8GB) Performance Hard Drive (ST2000LXZ01)
Samsung sh-224fb sata 24x oem pack internal optical drive
Superflower sf-650f14mt leadex full modular 650w 80 plus silver power supply unit
Nidec gentle typhoon 1850rpm 120mm pwm cooling fan
Coolermaster n200 mini tower chassis

My secondary PC with specs below, was mainly for casual gaming (before the pandemic), documentation and surfing the net.

AMD Ryzen 3 1200
ASRock AB350M
G.Skill F4 19200/2400mhz 8GB DDR4
Samsung SSD 850 EVO 250 GB
Western Digital WD20EARX-00PASB0 - 2TB 7.2K RPM 64MB Cache SATA 3.5" Hard Drive
Palit Geforce GTX 1050 StormX 2GB GDDR5 Graphics Card
Tecware F3 & FSP Hexa+ 450W

Now, I wish to upgrade my primary gaming pc to rtx 3080 and my secondary pc to play 1080p 244hz games as I'm working from home now.

I have the following pre-built model for my primary gaming pc but this is highly customizable from the builder. I'm also looking for good air flow that will blow air out the front and top of the case as it will be in a cabinet with length is 35cm (13.7 inch), width is 45cm (17.7 inch), and height is 43cm (16.9 inch) . I wanted to try sff but it looks like airflow is not that good. Also, is there a case that is built for pushing air out the front of the case or is it just a case of organizing the fans to blow out air from the front? There is a little opening out the back of the cabinet but the distance between the wall and the cabinet through the hole, is little.

cpu ryzen 5 3500x
mobo b450m msi bazooka max wifi
ram 2 x 8gb corsair vengeance rgb pro white (3200mhz)
gpu rtx 3080 zotac trinity
ssd lexar nm610 nvme ssd 250gb
hdd (will take from my primary pc)
psu superflower leadex III 850w gold rated psu
case nzxt h510 white
COOLER tecware mirage 240mm aio liquid cooler
ADDITIONAL 2 x inwin sirius loop argb fan + 1 x phanteks neon combo (2 argb strip)
wifi comes with motherboard + bt
S$2,370

Finally, is it a good idea to sell my secondary pc, use my primary pc as my secondary and get a new pc?

 

[NightRaven49]

is there a case that is built for pushing air out the front of the case or is it just a case of organizing the fans to blow out air from the front?

i think so long as the case has a mesh front, this should be possible. im no case airflow expert, but it seems logical to find a case where u can mount an equal number of fans on other sides of the case for intake as the front exhaust.

case nzxt h510 white

nzxt cases are notorious for having poor airflow

Finally, is it a good idea to sell my secondary pc, use my primary pc as my secondary and get a new pc?

i would say so. 970 is still quite capable these days, some more now is a good time to offload older and weaker gpus as prices are still pretty high.
also, 2.4k is an excellent deal for a 3080 system, most places can only snag 3060ti or 3070. usually 2.4 is the asking price for just the gpu too.

 

[FrostNinja]

Yeah that's what I thought on the case and overall price. Any recommendations on the case? I think topping up for a better case with good air flow is acceptable. Just need a good recommendation to pull the trigger.

I initially thought to upgrade both but since parts are expensive now, better just upgrade the main gaming one.