The bump multiplier in vraymtl, doesnt affect normalmaps with Triplanar, when rendering in GPU. Works fine with surprise surprise, cpu 
There was a similar thread here, but not triplanar related
https://forums.chaos.com/forum/v-ray…o-longer-works
Scene attached.
Maya 2022.3
V-Ray 5 for Maya, update 2.2 (v5.20.02, revision 31249 from Feb 9 2022)
Recommended nvidia drivers.
Triplanar Bump Multiplier.zip (54.9 KB)
If you put the material through a vraybump mtl then the multiplier on that works…but to be honest, personally i dont like the way the bump material comes after the actual material, really would prefer it if it was like in 3dsmax, where its a node that goes into the vraymtl.
Thanks for the report. I’ve logged the issue (internal bug-tracker id: VGPU-5818 ) for developer investigation. For now, use the mentioned workaround.
will do, thanks.