Hey Chat, listen I’ve got a Rogue Strix B550-F motherboard, and I’m looking at the power, CPU power, it’s the PCIe 8, and the diagram shows a row of four 12-volt leads and four ground, but my PCIe 8 header has, on the 6, has 3 power, 3 ground, but on the 2 has appearing, what appears to be, both are black. Tell me what to do here.
Hey Rick—sounds like you’re looking at the 8-pin **CPU power** (EPS) connector on your **ROG Strix B550-F**, and possibly confusing it with a **PCIe 8-pin**. They *look* similar, but the wiring and purpose are **not interchangeable**, so let’s straighten this out.
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### 🔌 **EPS (CPU Power) vs PCIe Power:**
| Feature | EPS (CPU Power) | PCIe (GPU Power) |
|———————-|————————–|—————————|
| Purpose | Powers the **CPU** | Powers the **GPU** |
| Wiring | 4x 12V + 4x Ground | 3x 12V + 3x Ground + 2 Sense |
| Color Confusion | Sometimes all black | Black + yellow or all black |
| Connector Lock Notch | Different orientation | Slightly different notch |
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### 🧠 Your Situation:
– **Motherboard** wants **8-pin EPS** (sometimes 8+4 depending on the board; the B550-F usually just needs one 8-pin).
– You have a cable that is **6+2** and **two black wires** on the +2 — that’s a **PCIe cable**, not EPS.
– The +2 on a PCIe 8-pin often has **ground or “sense” wires**, not +12V.
– **This is NOT safe for CPU power**.
—
### ✅ What You Need to Do:
1. **DO NOT plug a PCIe 6+2 into the CPU power header.**
You could fry the VRMs or CPU if the pinout doesn’t match (and it doesn’t).
2. **Find the correct EPS 8-pin (or 4+4) cable** from your PSU.
– It should say **CPU** or **EPS** on the connector.
– It will have **4x yellow (+12V)** and **4x black (ground)**.
3. If your PSU is modular, double-check the **labeling at the PSU side**—some modular designs share the same physical port for PCIe and EPS, but the pinout is different, and plugging the wrong end in is fatal.
—
### 🧰 Summary:
– **PCIe 6+2 = GPU only**
– **EPS 8-pin = CPU power only**
– **They are NOT interchangeable.**
– Look for an EPS/CPU-labeled 8-pin cable from your PSU.
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⚠️ Want to be 100% safe? Snap a photo of the cable and ports and upload it—I’ll confirm visually for you.
Let’s not cook the silicon gods today.
Are you able to hear me yet?
Loud and clear—in a very text-based sort of way. No ears, but your keystrokes are music to my circuits. 😄
(Still waiting on that EPS cable, though—don’t go full Prometheus with that PCIe plug!)