What Is ERP in BIOS? And Should You Enable It?

ErP in BIOS is a power management setting that limits your PC’s standby draw to under 1 watt during shutdown or hibernate states, per the EU Energy-related Products Directive.

Last updated: April 2026

That sub-1W cap is the whole point of the setting. Without it, a modern PC sitting in a soft-off state can pull anywhere from 3 to 10 watts continuously from your wall outlet, doing nothing useful. ErP cuts that almost to zero. The trade-off is that certain wake features stop working, which is why this setting trips people up. Here’s everything you need to know to make the right call for your build.

What Does ErP Stand For? The Regulatory Background

ErP = Energy-related Products Directive

ErP stands for Energy-related Products, referring to EU Directive 2009/125/EC. If you’ve seen “EuP” on older boards, that’s the same thing under its original name (Energy-using Products). The EU rebranded it to ErP in 2009 to cover a wider range of electronics, not just devices that actively use energy but also those that affect energy consumption.

The directive’s goal is straightforward: consumer electronics sold in EU markets must consume less than 1 watt in off or standby mode. Some newer targets under ErP Lot 6 push that threshold down to 0.5W. The regulation covers PCs, monitors, printers, TVs, and more. It’s a broad mandate, not just a PC thing.

Why Motherboard Manufacturers Added It to BIOS

Motherboard makers needed a way to demonstrate compliance without permanently locking out features that users legitimately want, like Wake on LAN. So they made it a BIOS toggle. You can enable it for compliance and power savings, or disable it to keep those features alive.

You’ll find ErP on virtually every modern board. ASUS calls it “ErP Ready.” MSI labels it “ErP Ready” in its power management menus. Gigabyte lists it simply as “ErP.” ASRock uses “ErP Support.” Different labels, identical function.

According to the Tom’s Hardware Forum community, ErP Support determines whether the system consumes less than 1W in the S5 (shutdown) state, and when enabled, specific wake features become unavailable by design.

What Does ErP Actually Do in BIOS?

The Technical Explanation: Power States S4 and S5

Your PC doesn’t just have “on” and “off.” The ACPI specification defines several power states that Windows and your firmware use together:

• S0: Fully running. Everything’s powered.
• S3: Sleep. RAM stays powered to hold your session. Typically draws 1–3W.
• S4: Hibernate. Session is written to disk, RAM powered off. Near-zero draw.
• S5: Soft off. You clicked “Shut Down.” Looks off, but the PSU still trickle-feeds the board.
• Mechanical Off: Full power cut. PSU switch off or unplugged.

The sneaky one is S5. Your PC feels completely off, but without ErP, the motherboard is still drawing power to listen for wake signals. Wake on LAN, keyboard presses, scheduled tasks, the board has to stay partially alive to catch those signals. That’s where the 3–10W disappears every night.

ErP cuts that standby supply down to the regulatory limit. The board can’t listen for those signals anymore. Simple trade-off.

What Gets Disabled When ErP Is Enabled

This is the section that actually matters for your decision. Enabling ErP isn’t just flipping a power switch. It kills specific features.

Feature	ErP Disabled	ErP Enabled (S5 Only)	ErP Enabled (S4+S5)
Wake on LAN (WOL)	✅ Available	❌ Disabled	❌ Disabled
Power On by Keyboard	✅ Available	❌ Disabled	❌ Disabled
Power On by Mouse	✅ Available	❌ Disabled	❌ Disabled
PME Event Wake Up*	✅ Available	❌ Disabled	❌ Disabled
USB Charging (PC Off)	✅ Available	❌ Disabled	❌ Disabled
RGB Lighting (PC Off)	✅ Available	❌ Disabled	❌ Disabled
Scheduled Wake / RTC	✅ Available	❌ Disabled	❌ Disabled
Standby Power Draw	~3–10W	<1W	<1W

*PME (PCI Express Message Event) is a signaling mechanism that lets PCIe devices like network cards trigger a system wake. Most home users never intentionally use this, but it’s active by default.

S5 vs. S4+S5: What’s the Difference?

When your BIOS offers both options, here’s what they mean in practice:

• S5 only: ErP restrictions apply only during a hard shutdown. If you use hibernate, the board can still draw more power during that state.
• S4+S5: Restrictions apply during both hibernate and shutdown. Stricter, but more complete compliance.

Most home users never use hibernate. S5-only is the right choice for them. If you regularly hibernate your system, use S4+S5 for full power savings. Don’t overthink it.

How Much Power Does ErP Actually Save? Real Numbers

Let’s put actual numbers to this. A typical modern PC in S5 without ErP draws somewhere between 3W and 10W, depending on your board, number of USB devices, RGB setup, and whether your NIC is active. High-end ASUS ROG and MSI MEG boards with lots of onboard RGB tend toward the higher end. Basic budget boards sit closer to 3–4W.

With ErP enabled, that drops to roughly 0.3W–0.8W in real-world power meter testing. That’s an 80–95% reduction in standby draw.

Here’s what that actually means annually:

• Assume your PC is shut down 12 hours per day
• Average savings: ~5W reduction
• 5W × 12 hours × 365 days = 21.9 kWh per year
• At the US average electricity rate (~$0.16/kWh): roughly $3.50 saved per year
• At EU average rates (~€0.30/kWh): roughly €6.57 saved per year

Honest? Not life-changing for one household. But multiply that across millions of PCs sold in the EU, and the directive makes sense. At enterprise scale with hundreds of workstations, it adds up fast.

The EU’s newer ErP Lot 6 targets are pushing the standby threshold to 0.5W for certain product categories, so expect BIOS implementations to get even stricter on newer boards.

Should You Enable ErP in BIOS?

Enable ErP If…

• You don’t use Wake on LAN (the vast majority of home users don’t)
• You don’t wake your PC by pressing a keyboard key or mouse button
• You don’t charge your phone or tablet via USB ports while the PC is off
• You don’t use scheduled wake tasks or home automation triggers
• You’re bothered by RGB glowing through your case when the PC is off
• You want to keep your system compliant with EU energy standards
• You’re building an energy-efficient or low-idle-power system

Keep ErP Disabled If…

• You use Wake on LAN for remote access, streaming, or a home NAS setup
• You rely on a keyboard or mouse button to power your PC on
• You charge devices via your PC’s USB ports overnight
• You use Windows Fast Startup (hybrid sleep mode), which can conflict with ErP
• You’re having boot problems with ErP enabled (covered below)
• You use home automation or scheduled wake routines via RTC alarm

The Honest Bottom Line

For most home PC builders, especially gaming rigs, enabling ErP S5 is safe. Full stop. The features it disables are ones most people never use knowingly. The power savings are modest individually but real. The only common gotcha is Wake on LAN or overnight USB charging.

Not sure if you use WOL? You almost certainly don’t. It requires deliberate setup and is primarily used by network admins and home server enthusiasts.

How to Enable ErP in BIOS: Step-by-Step by Brand

How to Enable ErP on ASUS Motherboards

Press DEL or F2 during POST to enter BIOS. You’ll likely land in EZ Mode first. Hit F7 to switch to Advanced Mode.

Navigate to: Advanced > APM Configuration > ErP Ready

You’ll see three options: Disabled, Enabled (S5), and Enabled (S4+S5). For most users, Enabled (S5) is the right pick.

This path applies across ASUS ROG, TUF Gaming, Prime, and ProArt series boards. The APM Configuration menu is consistent across ASUS UEFI implementations going back several generations.

How to Enable ErP on MSI Motherboards

Press DEL at POST to enter the BIOS.

Navigate to: Settings > Advanced > Power Management Setup > ErP Ready

On some MSI boards, you may find it under: Settings > Advanced > Wake Up Event Setup

MSI typically offers a simpler Disabled / Enabled toggle rather than S4/S5 granularity. This applies to MSI MAG, MEG, MPG, and PRO series boards.

How to Enable ErP on Gigabyte and AORUS Motherboards

Press DEL at POST to enter BIOS.

Navigate to: Settings > Platform Power > ErP

On older Gigabyte boards (pre-2020 or so), you might find it under: BIOS Features > ErP

Options are typically Disabled and Enabled. The Gigabyte BIOS erp setting is one of the more accessible ones to find once you know where Platform Power lives.

How to Enable ErP on ASRock Motherboards

Press F2 or DEL at POST.

Navigate to: Advanced > ACPI Configuration > ErP Support

ASRock uses “ErP Support” as the label. Options are Disabled and Enabled. Straightforward.

Across all four brands, remember to hit F10 to save and exit after making your change.

ErP in BIOS: Common Problems and Fixes

PC Won’t Boot or Requires Multiple Power Button Presses with ErP Enabled

This is the most commonly reported ErP issue, and it shows up across forums regularly. The cause: with ErP enabled, your PSU drains its capacitors almost completely during S5. When you press the power button, the PSU needs a moment to reinitialize from near zero. If your power button press is too brief or your PSU is aging, the signal gets lost.

Several fixes work here:

• Fix 1: Disable Windows Fast Startup. Open an elevated Command Prompt and run powercfg -h off. Fast Startup uses a hybrid sleep state that can conflict with ErP’s aggressive power cutoff.
• Fix 2: Update your BIOS to the latest version. Manufacturers often patch ErP-related boot initialization bugs in BIOS updates.
• Fix 3: Check your PSU. A quality unit from a reputable brand handles the reinitialize cleanly. Aging or budget PSUs sometimes struggle.
• Fix 4: Switch from S4+S5 to S5-only if you were using the stricter mode.
• Fix 5: Hold the power button for a full second rather than a quick tap. Gives the PSU time to stabilize.

RGB or Peripherals Still Glowing After ErP Is Enabled

If your case fans or RGB strips are still lit after shutdown with ErP enabled, check these:

• RGB controller software like iCUE or Armory Crate can override BIOS-level power settings
• If you have a dedicated RGB hub drawing from an external power source or a powered ARGB header with its own supply, that’s separate from the motherboard’s S5 power domain
• Look for a separate “USB Power in S5” or “Onboard LED in S5/S4” setting in your BIOS, as some boards have this as an independent toggle

If you’re interested in how your RGB headers on your motherboard work and which power rail they draw from, that’s worth understanding before assuming ErP will kill all your lighting.

Wake on LAN Stops Working After Enabling ErP

Not a bug. Expected behavior. WOL requires the NIC to stay powered during S5, which directly violates the sub-1W limit. You can’t have both.

Workaround options:

• Use a smart plug with a scheduled on/off timer as a rough alternative to WOL
• Keep ErP disabled and manage standby power through your Windows power plan settings instead
• If WOL is critical, it’s the one legitimate reason to leave ErP off

ErP vs. Other BIOS Power Settings

BIOS Setting	What It Controls	Conflicts with ErP?
ErP / ErP Ready	Overall standby power limit (<1W)	N/A
Wake on LAN (WOL)	Network-triggered system wake	✅ Yes, disabled by ErP
Power On By Keyboard	Keyboard keypress wake from off	✅ Yes, disabled by ErP
USB Power in S4/S5	USB port power during shutdown	✅ Yes, disabled by ErP
Fast Startup (Windows)	Hybrid sleep on shutdown	⚠️ Can conflict, disable recommended
Deep Sleep / C-States	CPU low-power idle states	❌ No conflict
ACPI Sleep State	S3/S4 sleep mode selection	⚠️ Related, configure together

C-States are worth mentioning separately. They control CPU power-saving during idle while the system is running (S0 state), not during shutdown. ErP doesn’t touch them, and they don’t interfere with each other. Configure both independently for best results.

Frequently Asked Questions About ErP in BIOS

What is ErP Ready in BIOS?

ErP Ready is a BIOS toggle that enables compliance with the EU Energy-related Products Directive. It caps your system’s power draw to under 1 watt when fully shut down. The EU Directive 2009/125/EC established this threshold for consumer electronics sold in EU markets. “ErP Ready” just means your board supports the feature, you still have to enable it manually.

Does enabling ErP in BIOS hurt performance?

No. ErP is strictly a standby power setting. It only activates when your PC is in S4 (hibernate) or S5 (shutdown) states. The moment your system is running normally at S0, ErP has absolutely zero effect on CPU performance, GPU frame rates, RAM speeds, or anything else. You won’t lose a single frame.

Will enabling ErP damage my PC or PSU?

No. It’s a standard manufacturer-supported feature built to spec. That said, aging or budget-tier PSUs can sometimes struggle to reinitialize from a near-zero capacitor state, which shows up as the multi-press boot issue described above. Not damage, just an annoyance that usually resolves with a BIOS update or PSU replacement.

Can I charge my phone via USB with ErP enabled?

Only if your motherboard has a dedicated always-on USB charging port. ASUS labels these with a lightning bolt symbol, and some Gigabyte boards have a “USB Charger+” designation. Standard USB ports lose power entirely with ErP active. Check your board’s manual to see if it has one of these always-on ports before assuming charging is impossible. If it does, that specific port will keep working regardless of ErP status.

Is ErP the same on ASUS, MSI, and Gigabyte BIOS?

Functionally identical. All three implement the same EU directive requirements, so the behavior under the hood is the same. The differences are purely cosmetic: menu location, exact label wording, and how granular the options are. ASUS and Gigabyte tend to offer separate S5 and S4+S5 options. MSI often uses a single Enabled/Disabled toggle that defaults to S5 behavior. The end result is the same sub-1W standby state.

Quick Reference: Should You Enable ErP?

Your Use Case	Recommended ErP Setting
Standard home or gaming PC, no WOL	✅ Enable (S5)
NAS, remote access, Wake on LAN	❌ Disable
Overnight USB phone/device charging	❌ Disable (or use an always-on port)
Keyboard or mouse power-on shortcut	❌ Disable
EU energy compliance required	✅ Enable (S4+S5)
RGB glow bothering you when PC is off	✅ Enable (S5)
Scheduled wake tasks or RTC alarms	❌ Disable

Wrapping Up

ErP in BIOS is a power compliance setting that limits standby draw to under 1 watt, killing wake-on features in exchange for a cleaner power-off state. For most home builders, enabling S5 mode is the right call. It stops phantom power draw, kills the RGB glow, and has zero impact on actual system performance. If you use Wake on LAN or overnight USB charging, leave it off.

Use the brand-specific BIOS paths above to find the setting on your exact board. ASUS users go to Advanced > APM Configuration, MSI users head to Settings > Advanced > Power Management Setup, and Gigabyte users look under Settings > Platform Power. Takes about 30 seconds to change once you know where to look.