Start from your GPU maker’s recommended PSU wattage, then pick a Seasonic fully modular 80 PLUS Gold unit in the 750 W / 850 W / 1000 W band that also names the ATX 3.x / PCIe 5.x support your graphics card needs. Do not invent a wattage from a random online calculator — use the GPU guidance and sensible headroom.

Shop in Electronics and Computer accessories. Sibling overview: 80 PLUS Gold Modular PSUs for AU PC Builds.

Direct answer — which wattage band?

Band Typical use (guidance only) Live Seasonic examples on Darrah Opens
750 W Mid-range GPU builds where the vendor recommends around this class Focus GX-750 V4, Core GX-750, Focus GX-750 White
850 W Higher GPU tiers / more headroom for CPU + multi-drive Focus GX-850 V4, Core GX-850, Focus GX-850 White
1000 W High-power GPUs, heavy creator loads, future-proofing within case limits Focus GX-1000 V4, Vertex GX-1000 White

Always re-check the live title for ATX 3.0 / ATX 3.1 / PCIe 5.1 wording and modular cable set.

What “ATX 3.0 / 3.1” is doing on the label

Newer GPUs can pull sharp power spikes and may use high-power PCIe 5-style connectors. When a Darrah Opens Seasonic title includes ATX 3.1 / PCIe 5.1 (Focus GX V4 examples) or ATX 3.0 (white Focus / Vertex examples), read the product page for:

  • Included GPU power cables
  • Whether adapters are required for your card
  • Continuous wattage rating

If your GPU still uses multiple legacy 8-pin PCIe plugs, a Gold modular ATX 3.x unit can still be appropriate — match cables to the GPU manual.

Focus GX V4 vs Core GX vs White / Vertex lines

Line (examples) Why builders look
Focus GX V4 (750 / 850 / 1000) Fully modular, 80 PLUS Gold, ATX 3.1 / PCIe 5.1 named on titles
Core GX (750 / 850) Gold full modular with ATX 3 naming on titles — compare feature set on each page
Focus GX White (750 / 850) Same wattage class with white chassis for show builds — see white setup expansion draft
Vertex GX White (1000 / 1200) Higher wattage white Gold modular options on the computer-accessories collection

This guide intentionally does not invent AUD prices — compare current pricing on each product page.

Choosing 750 vs 850 vs 1000 without guessing

  1. Read the GPU vendor’s recommended PSU wattage for your exact card.
  2. Add allowance for a power-hungry CPU, multiple drives, and RGB/fans.
  3. If you sit near the recommendation and run long renders or hot-summer gaming sessions, step up one band.
  4. Confirm case ATX depth — the Focus GX-750 White listing notes a compact 140 mm depth among its specs; always check the SKU you buy.
  5. Prefer fully modular flat cables for airflow in mid-towers.

Avoid

  • Undersizing because “Gold is efficient”
  • Jumping to extreme wattages your case/cables cannot use cleanly
  • Ignoring connector generation for PCIe 5 GPUs

Australian practicalities

  • Mains are 230–240 V; modern ATX units are typically full-range — confirm the label (Focus GX White lists 100–240 V input on its page).
  • Dust and heat: modular cabling + filtered intakes help; clean filters in summer.
  • Noise: fan curves differ by series — the white Focus GX listing notes S3FC fanless until 30% load language; verify on your SKU.

Pre-purchase checklist

  • GPU maker wattage met or exceeded
  • 80 PLUS Gold (or higher if you deliberately step up)
  • Fully modular for your cable plan
  • ATX 3.x / PCIe 5.x named when required
  • Depth fits the case
  • White vs black chassis decided for build aesthetic

Who Seasonic ATX 3 wattage bands suit

Aussie PC builders matching GPU maker PSU recommendations to Focus GX V4 / Core GX / white Vertex modular Gold units in the 750 / 850 / 1000 W conversation — plus white 1200 W Vertex where listed.

Headroom without invented calculators

Start from the GPU recommendation, add drives and fans realistically, then step up a band if you run a power-hungry GPU and heavy CPU together. Do not invent continuous-watt charts — use the maker card and the Seasonic page wattage.

Cable kits and case fit

Fully modular Focus / Vertex units help small ATX and dual-chamber cases — connect the 12V-2x6 / PCIe leads your GPU needs as named on the Seasonic page, and leave unused modular cables bagged. Confirm the PSU depth (compact ~140 mm class on many Focus listings) clears your case’s PSU tunnel.

FAQ

Is 850 W always safer than 750 W?

Safer only when your GPU recommendation and system draw justify it. Oversizing without need mainly costs money and case space.

Do I need ATX 3.1 specifically?

Need it when your GPU ecosystem expects that generation of transient handling / native high-power connector support. Otherwise ATX 3.0 Gold modular units may still suit — match the card manual.

Focus GX V4 or Core GX?

Compare the live pages for the wattage you need. Both appear as Gold full modular with ATX 3.x naming; features and pricing differ by SKU.

Where is the white modular tidy-cable guide?

See the white modular PSU setup expansion draft in this batch, including Focus GX White and Vertex GX-1000 White links.

Where do I shop Seasonic on Darrah Opens?

Computer accessories and the product URLs above; also the primary 80 PLUS Gold modular PSU guide.

What does 80 PLUS Gold mean on these units?

It is an efficiency certification tier printed on the Seasonic Gold listings — not a wattage upgrade by itself.

Why does ATX 3.x / PCIe 5.x matter?

Newer GPU power connectors and transient handling are part of the ATX 3.x story on Focus GX V4 and related pages — match to your GPU maker guidance.

Is 1000W always safer than 750W?

Not automatically. Oversizing is fine within reason; buying 1000W for a low-power office PC wastes money and case space. Follow GPU recommendations first.


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