ASRock's X299E-ITX/ac is just simply not your standard motherboard. The mITX form factor should be the first indicator for you. As such, a standard review almost doesn't apply. This is highly specialized gear, and getting it all up and running properly requires even more highly specialized gear in the form of cooling and memory, to start. Neither is easy on the wallet. If you have a set budget for your building needs, this board probably just not for you. To me, this is a real enthusiast product for Intel's X299 platform, and as such, it sets itself apart from the rest, offering something that pretty much no one else does; near-complete functionality of the X299 platform in the rather diminutive mITX form factor. You simply just shouldn't have a board that small with this socket, but here were are, and the board is widely available, with many of our fellow review sites having gotten their samples too.

Testing such a board for performance, other than to verify that things are working correctly, just doesn't make sense. If what you want is X299 mITX, I don't think performance is really going to matter to you that much as long as it works right. How other boards perform isn't going to matter either because they don't offer what this board does, at all. You most definitely can call this board a niche product.

I did take the time to test many CPUs in this board's socket and was pleased with the results; it all works exactly as expected. Yet of course, there are some caveats to this; you need expensive RAM and expensive cooling. However, that should have been a given from the start because of the board's truly small size. Intel's X299 i9 CPUs support 2666 MHz memory by default, and getting four SO-DIMM sticks at that 2666 MHz speed is going to cost you roughly $500. The board is $400. A 7900X is roughly $1000. We haven't even gotten to drives, a power supply, cooling, or case yet, and we're already closing in on $2000, and once done, we're likely going to be at over $3000, depending on which VGA and drives you choose. This ASRock X299-ITX/ac board is the base for a rig that can easily cost you $5000 and beyond, and meanwhile, you could stuff it into a shoebox. Price-per-square-inch has never been so high. Excuse me for a moment while I go catch my breath.

There are some things here I do not like very much. The audio lacking multi-streaming is annoying, and the thinness of the front-panel add-in card is scary. That card could definitely use a few more layers or some sort of brace to increase rigidity. The pin headers for things like fans and front panel and audio are all over the place, so wiring this thing and keeping it looking good is rather difficult. Yet even so, it all works so wonderfully well together, and not only does it work well, it works extremely well, and so much so that you can get a good overclock out of this little board easily. If you want the best and don't want it to take up a lot of space on your desk, you really can't look anywhere else. It'll leave your wallet crying, but does that even matter?