Quick Answer
Treat Corsair iCUE H150i in Phanteks NV5 as a measurement-first fit, not an automatic yes. a 360 mm AIO class cooler with roughly a 52 mm radiator-and-fan stack on many versions. If your DDR5 is taller than about 35 to 44 mm, choose low-profile modules or a front radiator mount before forcing the roof mount.
Measure the DIMM zone first
The safe approach is to compare RAM height, motherboard heatsink height, and the cooler stack before checkout. Kingston Fury Beast DDR5 and Corsair Vengeance DDR5 are easier fits than tall RGB kits in cramped roof mounts. Broad local DDR5 kit pricing often sits around R1,500 to R4,500, while 360 mm AIO coolers can sit from about R2,500 to R6,000 depending on screen, fans, and warranty tier.
Top mount versus front mount
A top-mounted 360 mm radiator keeps tubes tidy but crowds the motherboard edge. A front mount can free the DIMM area, yet it may reduce GPU length clearance and change airflow. Builders in SA should also check the exact case revision, because small roof offsets and fan brackets can decide a fit by only a few millimetres.
Builder checklist
Use a tape measure, not only product photos. Confirm radiator thickness, fan thickness, motherboard model, RAM height, GPU length if relevant, and the direction of tubes or power cables. A neat build should let you remove one DDR5 stick later without stripping the entire cooler.
FAQ
What DDR5 height is safest for this fit?
Low-profile DDR5 around 35 mm is the safest starting point. Tall RGB modules around 44 mm or higher can still work, but they need a confirmed case and cooler layout.
Should I buy the cooler or RAM first?
Choose the case and cooler layout first, then pick memory that leaves a few millimetres of service space. That avoids paying R1,500 to R4,500 for a part that technically fits but is difficult to maintain.
Does this affect gaming FPS?
Clearance itself does not add FPS, but clean airflow can protect boost clocks. A cramped build that runs 5 to 10 degrees hotter may become noisier and less stable under long 1440p gaming sessions.
Pro Tip
Before checkout, compare the case manual, motherboard layout, and exact RAM height on one note; if any number is missing, choose the lower-profile part.