If both are an option, the X63 is worthwhile and offers a couple of advantages:

- cheaper than X62
- fewer cables than X62
- illuminated front now rotatable
- polished cooling plate for better contact with the heat dissipation plate (the "lid" of the processor)
- manufacturer's warranty now 6, instead of 5, years

Functionally, they are almost identical, although the 7th generation pump from Asetek is installed in the X63, compared to the 6th generation in the X62. Even with the 6th generation, the impeller of the pump was made of metal instead of plastic - which is why both run very reliably.

Especially for the H510 I would recommend the X63 - due to the lack of space in the X62 you have to decide whether the hoses run directly above the graphics card (and are thus exposed to the heat of the back plate of the card) or whether you a) switch off the illumination from the logo of the pump, or b) accept to show the logo upside down, so that the water hoses run under the upper housing fan.

In summary, the X63 reissue of the X62 is a marginal improvement that is even cheaper. For someone who doesn't own a water cooler yet, this would be 10/10 my recommendation. Those who already own an X62 will not notice any significant increase in performance, apart from the aforementioned aesthetic changes.

Hope that helps!

the X63 is exactly the same size as the X62... so there is no difference in dimensions... both fit in your H510 Elite... X63 is the successor of X62... but nothing has changed except the name... the X63 simply has a new HUE 2 connector for additional RGB settings.