I'm upgrading my current AM4 system instead of building a completely new PC because component prices are high. The planned changes are a Ryzen 5 5600X to a Ryzen 7 5800X3D with a be quiet! Dark Rock Pro 5, a GTX 1660 Ti to an ASUS Prime Radeon RX 9070 XT OC, and 16GB of G.Skill DDR4-3200 CL16 to 32GB of Corsair Vengeance LPX DDR4-3200 CL16.
The rest of the system is a Gigabyte B550 AORUS Elite V2 motherboard, Cooler Master MWE Gold 750W fully modular PSU, and Samsung 980 1TB SSD. Will these upgrades work well together?
The graphics card has three 6+2-pin PCIe power connectors, while my PSU came with two PCIe cables. Should I buy another cable so every connector has a separate cable, or is it safe to use the connectors on the existing cables, including daisy-chained plugs? I'd also appreciate any other upgrade or installation tips.
4 Answers
The upgrade is broadly compatible, but update the motherboard BIOS before replacing the 5600X so it supports the 5800X3D. After installing it, enable the memory’s XMP/DOCP profile so the RAM runs at 3200 MT/s. Also check the 9070 XT’s physical length, thickness, and airflow requirements in your case.
The Dark Rock Pro 5 will handle the 5800X3D, although it may be more cooler than you need and could be expensive for this CPU. A good mid-sized tower cooler would also be adequate. For the memory, two matched 16GB sticks are usually preferable to combining separate kits, even when their specifications match. Mixing the old and new kits may work, but you might need to lower the speed or adjust settings if it isn’t stable.
A 750W Gold unit should be okay for the listed parts, assuming it’s healthy and has the required PCIe connectors. An 850W unit would provide more headroom, but it isn’t automatically necessary. The 5800X3D and 9070 XT should make a substantial improvement over the 5600X and 1660 Ti, especially at higher resolutions.
The 750W PSU should be sufficient for this setup. You don’t need to buy a random extra modular cable—modular cables aren’t universally interchangeable, so only use one specifically made for that exact PSU model. Your two included PCIe cables have multiple connectors, so using two connectors from one cable and one from the other is generally fine. Make sure every plug is fully seated and avoid using adapters unless the graphics-card manufacturer explicitly requires one.
That clears up the cable question. I’ll use the original cables and double-check that any replacement cable is specifically compatible with my PSU.

I got the Corsair kit at a very good price, so I’m going with it. I’ll test the memory thoroughly rather than assuming two separate kits will behave exactly like one matched kit.