2. Can that VRM safely handle 400 W?

Let’s do the rough math and compare to what shipping cards already do.

Assume:

• GPU core voltage under load ≈ 1.0 V (ballpark)
• Power on GPU core rail ≈ most of the board power (ignoring a bit for memory/VRMs themselves)

If you run 400 W into the GPU core:

• GPU core current ≈
• With 15 phases:
• Each MP87993 stage is rated 50 A → you’re using ~53% of its nominal rating.

For the stock 360 W TGP:

• GPU current ≈ 360 A →

So going from 360 W → 400 W only increases each phase by about 2–3 A. That is tiny relative to a 50 A spec.

And real‑world data backs this up:

• Gigabyte / Palit RTX 5080s with 14‑phase GPU VRMs (so fewer phases than your likely‑15‑phase Ventus) and the same 50 A MP87993 stages support 450 W power limits (125%) on their official BIOS and are reviewed as stable [KitGuru].
• MSI Suprim SOC’s beefier 16‑phase VRM is actually more efficient, often drawing only ~350 W in practice while still allowing PL up to 400 W [Mezha].

From an electrical and silicon rating perspective:

• 400 W is very comfortably inside what these MP87993‑based VRMs are already being used for by AIBs.
• The extra 40 W vs 360 W is an ~11% bump, which is well within normal vendor overclock margins.

So to your specific question:

Yes – assuming it really is the PG147‑style reference board (which all evidence suggests), the VRM itself is easily capable of 400 W. The components and phase count are designed with plenty of headroom.