For the cpu cooler part, comparing to the stock cooler of 2400g, could the L9a help to extend the longevity of the apu and the a300 motherboard, also help increase the performance of apu , or it just depend on luck?
For choosing the ram, as i know the price of a 8gb 3200mhz c16 ram could be a double of the price of a 8gb 2666mhz cl19/ 2400mhz cl16 ram, or even higher, and i am on a budget to build this pc for programming , entertaining and some casually gaming
how to determine a ram that have a large overclock headroom? is it better to stick to a low CL ram , something like 2400mhz cl16 , and try to overclock it to 3200 cl16?
Also, any suggestions on the nvme drive for installing os and other programs?
I just posted Hardware unboxed review of the 3400G. Steve was able to get over 1900 in Cinebench R20. I am getting 1865 consistently. Trying to tweak settings in the BIOS keeps dropping the score. If you're going for an absolute budget build the 2400G for $99 is a great value and comes with a cooler that will fit (after the outer shroud is removed) and is under promo ATM with 3 months of XBox game pass.
The Noctua cooler will not improve performance. The A300 only allows RAM over clocking and multiple tests of my own and comments from other users suggests that power delivery may be an issue with sustaining boost clocks or achieving higher stable ram frequency and performance above DDR4-3333 @ 1.35v. The Noctua will make the A300 quieter and easier to take apart as the stock cooler barley fits in the case. The cooler that comes with the A300 is awful in comparison and I wish ASRock wouldn't have included it.
Between going with the 2400G and not buying the Noctua that would be a savings of almost $100.
Another thing to note is you've decided on the ADATA XPG SX8200 Pro. I really wanted that myself when putting together my A300, It just didn't make sense with this build. You can save a few more dollars and sacrifice little performance, with an intel 660P. The 1TB version can be found for $85 which would double your storage capacity or the 512GB can be found for $60.
I would have a hard time believing people would be able to tell the difference unless they where continually moving large files around.
RAM, however, makes a BIG difference and is the one area of the build I wouldn't compromise on. A friend of mine didn't want to spend the money on the lower latency DDR4-3200 GSkill CL18 (2x8) ram kit or worry about Over Clocking so he went with much cheaper crucial CL22 chip. His performance is still excellent.
That said it's completely possible that you could get lower speed ddr4-2666 1.20v kit, bump it to 1.35v in BIOS, and it will clock to 3200 or 3333 with out any issue with decent timings. For me, it was worth getting a kit with an advertised speed of least 3200 mhz as the speed affects every aspect of the systems performance and does double duty as 2GB of memory are automatically reserved for the iGPU. If your on an absolute low budget newegg has the GSkill ddr4-2666 CL19 kit on sale for $80 but the ddr4-3000 CL16 kit is $100 while the ddr4-3200 CL18 kit is still $150. It might not be worth an extra $70 but at the moment is it worth an extra $20 to insure a guaranteed floor and the potential to get the same performance as people are seeing with the 3200 kit in the A300?
In the end you have to do what's right for you and your build, based on your use case. I bought the A300 because it was an ultra small, easy to work on, portable machine. Otherwise, for not a whole lot more, I could have gotten a system like this that would be way more powerful then the APU for only a few bucks more:
pcpartpicker.com