Realtek showcased RTL8126, RTL8157, and RTL8251B 5 Gbps Ethernet solutions at Computex 2023, and the first Realtek RTL8126 5 Gbps Ethernet PCIe and M.2 adapters were introduced in 2024, shortly followed by RTL8157 5GbE USB 3.2 adapters.
The company has now unveiled upgraded solutions for 10 Gbps Ethernet networking at Computex 2025 with the RTL8127 10GbE PCIe controller and variants, the RTL8159 10GbE USB 3.2 Gen 2×2 controller, and the RTL8261C PHY for 10GbE switches.
Realtek RTL8127 10GbE PCIe NIC
Realtek RTL8127 specifications:
- Ethernet – 10Mps, 100Mps, 1000Mps, 2500Mps, 5000Mps, and 10Gbps
- Host interface – PCIe Gen4
- Features
- Modern standby
- Self loopback diagnostic
- Hardware ECC and CRC
- Power consumption – 1.95 Watts
- Package – 9×9 mm QFN88
The Realtek RTL8127 will be found in PCIe and M.2 cards, or directly soldered on motherboards or CPEs. The good news is the low power consumption, which should make cooling easier and cheaper (Realtek claims a $0.125 saving on heatsink) compared to competing 10GbE controllers.
Three other variants will also be offered. The RTL8127AP targets servers with DASH 1.2 remote management technology support, the RTL8127ATF for FTTx (Fiber) only, without support for 10/100 Mbps speeds, and a low power consumption of about one Watt, and the RTL8127AT is similar to the former but without fiber support.
The RTL8127ATG and RTL8127AT support either PCIe Gen 3 x2 or PCIe Gen 4 x1 for better compatibility with older motherboards.
Realtek RTL8159 10 Gbps Ethernet USB 3.2 controller
Realtek RTL8159 specifications:
- Ethernet – 10Mps, 100Mps, 1000Mps, 2500Mps, 5000Mps, and 10Gbps
- Host interface – USB 3.2 Gen2 x2
- Features
- CDC-NCM compatible
- UEFI PEX
- Hardware support for RSS
- MAC Address pass-through
- Power consumption – TBD
- Package – 8×8 mm QFN68
The RTL8159 will be integrated into USB Ethernet adapters, hub monitors, and USB docks.
RTL8261C PHY
Realtek RTL8261C 10GbE single PHY specifications:
- Ethernet Speeds – 10GBase-T, 5000Base-T, 2500Base-T, 1000Base-T, 100Base-Tx, 10Base-Te
- Interfaces – USXGMII/SFI (XFI), 5000Base-X, 5000Base-R, 2500Base-X, 1000Base-X, HiSGMII/SGMII
- Co0lab 5GbE PHY RTL8251B and 2.5GbE PHY RTL8221BN
- Power Consumption – 1.65 Watts
- Package – 8×8 mm QFN56
- Industrial grade option – RTL8261CI
The RTL8261C will be used in 5G CPE, PON, WiFi 6/7 routers, switches, and cable modems.
Pricing
While Realtek did not directly disclose pricing information, TechPowerUp reported that a representative insinuated that the new 10 Gbps chips would be less than double the price of Realtek’s current 5 Gbps chips. Considering a Realtek RTL8126 5 Gbps Ethernet PCIe and M.2 cards can be purchased for around $15, we might end up with similar to RTL8127 cards going for $30 to $40. It’s the same story for RTL8157 5GbE USB 3.0 adapters at about $15. Several cards and motherboards based RTL8127 are expected by Q4 2025, but we will probably get more choices later in 2026.
Thanks to TLS for the photos.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.
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I wonder what the idle power consumption is like.
What I find interesting here is that we’re talking about less than 2W for 10GbE over twisted pair. For a long time, 10G RJ45 was cooking your NIC. Thus if they’re now able to improve the phy on that point, other vendors should follow soon. While the transition from 100M to 1G was brutal 20 years ago with all vendors switching to GbE at the same time, 1G to 10G is almost non-existent, and it’s the first period where we’ve seen baby steps instead (2.5G, 5G). So I’m not sure we’ll see more than 10G over twisted pair for a very long while!