people allways like to disagree
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but I do think intel sould provide a stock cooler with all there CPU’s. Look at amd wraith prism cooler now I know we can’t really test it on intel but something like that in intel box would be a nice starter cooler for the cpu.
Having a stock cooler means you can also spread out the cost a bit more on your custom build. One less thing u need to buy at point of sale with cpu ram mobo normally as a base upgrade (I know there are other parts as well) having to buy cooler also will push the price up when u could wait a few weeks and buy the cooler you want. Most of us have to cut something to hit a price point.
a stock cooler is also good for first setup when testing out of the case exp for people with hard tube custom loop allows u to test before reassembling you’re whole system
also whilst a 9900k is a heat generator at oc levels at stock it’s pritty easy to cool really only when tour trying to get that last bit out of it.
but I also wished ryzen 3900x come with some sort of basic gpu inside also just something to show a display out so you don’t have to use my main card when testing outside the case.
but a very good air cooler or watercooling is very good advice though custom loops do have more moving parts and is prone to failure and leaks and compatibility issues and can be quite intimidating for first build though. Allways do your research and get advice from people. But I do recommend a Noctua nh-d15 now in black looks good and excellent cooling