[SOLVED] Radiator case compatibility help

[Kusky]

So originally I was going to get the Corsair 460x RGB case with a Kraken x62 cooler which has a 280mm radiator. But today I went into a PC shop and the guy there pointed out the case only supports 120mm; 240mm; 360mm (PC Part Picker compatibility didn't pick this up). So my confusion here (I'm a first time builder) is that, why does it say it can support 240 and 360, but not 280 if 360 is bigger?

My second question - A white version of the 460x says it CAN support 280mm, while the black case says it can't even though they have the same dimensions, name and model (by the looks of it)
Here is the page for the 460x black LINK
And here is the page for the 460x white LINK

So which is true, does the black case have an error in information which is why PC Part Picker didnt pick it up, is the white one incorrect, or are they actual different models inside even though they're named the same?

 

[Aeacus]

Well, to know PC case rad support, look it by the fan support, which translates to:
1x 120mm fan = 120mm rad
2x 120mm fan = 240mm rad
3x 120mm fan = 360mm rad

1x 140mm fan = 140mm rad
2x 140mm fan = 280mm rad
3x 140mm fan = 420mm rad

As far as the rad support on the top goes, TH review said this:

Hidden under a magnetic dust filter, the top panel also has room for a radiator. Unfortunately, the 1.1” of space above the motherboard doesn’t leave room for a radiator and fan stack, and the 140mm fan mounts are offset only around 0.6” from the motherboard’s surface. Those limitations will usually limit the top panel to a pair of 140mm x 25mm fans, or a 2x 120mm radiator and fan set hanging 1.4” (35mm) from the motherboard’s surface. Keep this limit in mind when purchasing RAM, or liquid-cooled voltage regulator water blocks.

source: https://www.tomshardware.com/reviews/corsair-crystal-460x-glass-mid-tower-atx-case,4908.html

When it comes to the official specs of Corsair cases, they are known to not include all possible combos. 2x examples: Corsair 760T V2 (black and white versions) and Corsair 750D (including Airflow Edition). On both cases specs page, there is stated that they doesn't support 420mm rad. Max is 360mm rad.
In reality, both cases support 3x 140mm fans at the top, making 420mm rad installation possible. I have both cases in use (Skylake and Haswell builds, full specs with pics in my sig) and i installed 3x 140mm exhaust fans at the top problem free. Also, there's plenty of space for rad and fans above the MoBo.
760T V2 Black specs: https://www.corsair.com/eu/en/Categories/Products/Cases/Graphite-Series%E2%84%A2-760T-Full-Tower-Windowed-Case/p/CC-9011073-WW
750D AF edition specs: https://www.corsair.com/eu/en/Categories/Products/Cases/Obsidian-Series%E2%84%A2-750D-Airflow-Edition-Full-Tower-ATX-Case/p/CC-9011078-WW