I'm trying to decide whether to spend about $50 on a used i7-9700K, around $200 on an i9-9900K, or put that money toward a completely new platform. My current system has an Asus Prime Z370-P, 32GB of ordinary DDR4, and M.2 storage. I mainly game, but I also compile code, do some game development, and expect to do more video editing and art work for my small business. The six-thread i5-8400F has become noticeable during compiling, and my secondhand RTX 2070 has had ongoing stability problems. The GPU also seems to be held back by the CPU, so I need to improve the processor before replacing the graphics card.
Newer options such as a current Intel or AMD platform would perform much better, but DDR5 and the motherboard costs make them difficult to fit into the budget. AM4 is another possibility, especially with a used Ryzen 5 5600 or 3600, although buying an X3D chip seems expensive enough that AM5 might make more sense. Would you take the inexpensive 9700K as a stopgap, pay extra for the 9900K, or save for a full platform upgrade?
5 Answers
The newer platforms are the best long-term answer, but the total cost matters: CPU, board, DDR5, and eventually a better GPU. Since your budget is tight and the graphics card is also unreliable, I’d avoid spending $200 on an old 9900K. Either grab the $50 9700K as a temporary extension or save everything for a complete modern build. The cheap stopgap is much easier to justify.
A used Ryzen 5 5600 with a B450 or B550 board is also worth considering. The 5600 is around the level of a 9900K in many gaming scenarios and is a substantial jump from the 8400F, while a used AM4 combo can be reasonably affordable. A Ryzen 5 3600 would be an even cheaper upgrade, though it makes less sense to spend heavily on AM4 now unless you find a particularly good used deal.
For roughly $50, the 9700K is the easy choice. It should be a clear improvement over the 8400F and lets you keep your existing motherboard and memory. The 9900K is only modestly faster in many workloads, so paying an extra $150 or more for it is hard to justify. Put the difference toward the eventual GPU or a full rebuild.
The 9900K is still a capable processor, but its price comes from being the fastest upgrade available for that socket rather than from offering great value. The 9700K gives you most of the practical benefit for far less money, and eight physical cores should help with your compiling and general productivity compared with the six-thread 8400F.
If you’re replacing the motherboard anyway, a DDR4 board with a 12th- or 13th-generation Intel CPU can be a good middle ground. A 12600K or 14600K would offer a much stronger boost for compiling, editing, and multitasking without forcing you to buy DDR5 immediately. The 12600K is especially attractive if it is substantially cheaper.
That’s the direction I’m leaning. If the 9700K still doesn’t meet my needs, I can build a new system later and reuse this one as a living-room or emulation PC.