I've already bought the main components for my new build because I found them on sale: a PNY GeForce RTX 5080 16GB ARGB OC, an AMD Ryzen 7 9800X3D, and 64GB of Crucial Pro DDR5-6400 CL40 memory in a 2x32GB kit. The RAM cost €600. I'm unsure whether CL40 is too slow for gaming, since I could instead buy 32GB of 2x16GB DDR5-6400 CL38 for about €350, though I'd prefer 64GB because I also do engineering work. Would the slightly higher latency noticeably hurt gaming performance, or is the 64GB kit still a sensible choice? I now need recommendations for a compatible power supply, motherboard, and CPU cooler. There's no strict budget, but I'd rather not pay a premium for features that won't matter. I also want a relatively compact case—smaller than my current older case, which has a lot of unused space—so I'm unsure how to check whether the graphics card and other components will fit. I'm open to a compact ATX or micro-ATX setup as long as it has good compatibility and cooling.
3 Answers
I wouldn’t wait on the memory, and CL40 isn’t a dealbreaker here. The higher capacity is useful for engineering workloads, while the latency difference will generally only show up as a small change in CPU-limited or 1% low performance. Keep the 2x32GB kit rather than trying to run four DIMMs; AM5 generally prefers two populated slots. Make sure the kit is stable with its EXPO profile, and if needed you can run it at a slightly lower speed such as DDR5-6000.
For the power supply, look for a high-quality ATX 3.1 unit with a native 12V-2x6 connector. Around 850W is usually appropriate for a 9800X3D and RTX 5080, while 1000W gives you extra headroom if the price difference is reasonable. For the motherboard, a good B850 or B650E/X870 board is enough; you don’t need the most expensive X870 model unless you specifically need its USB, storage, networking, or expansion features. An MSI MAG B850M Mortar-type board would suit a compact micro-ATX build well.
A large air cooler such as the Thermalright Phantom Spirit or Peerless Assassin class is more than capable for the 9800X3D and avoids the pump and radiator concerns of an AIO. If you choose a particularly small case, check the cooler-height limit first; some compact cases may require a shorter cooler or a 240/280mm radiator. A case such as the Lian Li A3 can fit a powerful graphics card with a micro-ATX board, but the available GPU length, thickness, PSU format, radiator placement, and cooler height all depend on the exact layout. A compact ATX power supply may fit, though an SFX unit can provide more room. Compatibility tools are useful, but for small-form-factor builds you should also compare the manufacturer specifications for every part directly.
I’m not looking for an extremely tiny system—just something less oversized than my current case. I’ll compare the GPU dimensions, motherboard format, PSU size, and cooler clearance before choosing the case.
That makes sense. I’d rather keep 64GB if the gaming impact is minor, especially since I’ll also use the system for engineering work.