reserved a1.large instances are about half the price of OVH's b2-7 instance. a1.xlarge are still cheaper (and larger). So you get more raw compute per dollar on AWS.
OVH dedicated instances start at about the size of an a1.metal instance, which is ~30% more than the comparable OVH instance, but you can get discounts in various ways.
Or you could use t4g.2xlarge, which is cheaper. There's no situation where OVH is 3x cheaper (I mean maybe if bandwidth is your thing, but IDK).
What?