I brought in the i9-9900K.
I brought in the i9-9900K.
This board supports models from the 6th and 7th generation only. The 9900k won't fit here.
Choose a 300-series motherboard such as H310, B360, B365, H370, Z370 or Z390. A Z-series board is best for full functionality—like supporting faster RAM speeds than DDR4-2933—and it’s more likely to include a VRM that can power the 9900K.
The 9900K is an outdated processor that’s not performing well anymore. Consider upgrading to something like the 13600K or a 7800x3D, as those options are more affordable compared to the 9900K’s high cost. It’s pretty clear the buyer went for a CPU from four generations ago.
It's likely the owner acquired it for enhancement to a current setup.
It varies by cost. If the person bought it for $100 from a friend, it’s a solid offer. You can find Z390 boards near $120 and DDR4 is very affordable these days—16GB options are available for about $40. That brings the total platform cost to around $260, matching the performance of a 12400 at a lower price. However, the amount spent influences value; spending over $200 doesn’t justify the purchase.