We are starting to see the signs of 1GbE finally ready to be phased out. A perfect example of that is the TRENDnet TEG-25GECTX adapter, or what is simply called the TRENDnet 2.5Gbase-T PCIe Adapter. As the product name states, this is a PCIe 2.0 x1 adapter that can handle 2.5GbE speeds. Price-wise, this adapter sells for under $50 making it a relatively inexpensive means to increase network performance. In our review, we are going to look at what that means for our readers.
TRENDnet TEG-25GECTX Hardware Overview
The most important side of the TRENDnet 2.5Gbase-T PCIe adapter is this shot. There is a single RJ45 port here that operates at 2.5GbE speeds. The adapter also operates at 100M and 1GbE speeds if you wanted to use an expensive adapter for legacy networking.
The card itself is tiny. It fits into PCIe Gen2 x1 slots. Practically, that means if you have a legacy Atom C2000 series or Xeon D-1500/ D-1600 series server, or a workstation with PCIe Gen2 or Gen3 x1 slots, you can use this adapter to add a 2.5GbE port.
The card itself is powered by a Realtek RTL8125 2.5GbE controller. Realtek NICs are everywhere. We are still waiting to see the Intel i225 NIC be used in volumes, but the Realtek solution is said to be less expensive and easy to integrate. You can see an example of this with just how sparse the small PCB is on the TRENDnet TEG-25GECTX.
One item we wish could be improved is the serial number/ MAC address label as well as the product identification label. These are found on the full height bracket for the NIC. The unit actually ships with a low-profile bracket as well. If you install the low profile bracket, it does not have these labels which means you do not have these important markings attached to the card. The labels are fine, they just need to be moved to the PCB.
This is one of STH’s smaller hardware overview pieces, and for a good reason. This is a relatively simple device. It seems like that is what TRENDnet is going for with their 2.5Gbase-T adapter. Something that is extremely simple and low cost.
TRENDnet TEG-25GECTX Setup
In Windows 10, the TRENDnet TEG-25GECTX was dead simple to set up. You plug in the adapter, and it connects with a DHCP address.
There are updated drivers compared to what is now shipping with Windows 10, but having easy plug-and-play functionality is nice. You can see that the card immediately connected to our multi-gig switch and negotiated at 2.5Gbps speeds.
There are a number of features such as VLAN tagging and Jumbo Frames that one may want to change after setting up the NIC.
Windows 10 setup, as of this review, is as simple as it can be. This is truly plug-and-play. For those of our readers that remember setting up 10Mbit networks in Windows 95 and 98, this is the experience we wanted twenty years ago.
Linux was a bit more difficult. We tested the NIC in both Ubuntu 18.04 LTS and 19.10. Both ended up requiring a driver update to work.
We are only a few months from the Ubuntu 20.04 LTS release where we expect these NICs to be out-of-the-box functional.
If you are in Windows, this is exactly the solution you want. As a note, newer Linux kernels will see updated Realtek driver support. Realtek sells so many low-cost NICs that are in cards like these and directly on motherboards that support will come as newer drivers are integrated. Here is the current driver page.
TRENDnet TEG-25GECTX Performance
We tested the unit directly attached between two Windows 10 PCs each equipped with TEG-25GECTX NICs. We also pushed these through a multi-gigabit switch and saw the same results within a 0.7% margin of error. We also used the speed setting to manually drop speeds from 2.5GbE to 1GbE.
This is really a big impact. If you have a multi-gig switch or simply want to directly attach two machines such as a NAS and a server or workstation, then this is a greater than 2x network performance boost for under $50 per node. We also tested these speeds on 10GbE SFP+ switches using MikroTik S+RJ10 SFP+ to Nbase-T adapters and linked at 2.5GbE speeds with similar results.
TRENDnet TEG-25GECTX Power Consumption
The official spec sheet for the TRENDnet 2.5Gbase-T adapter says that it uses a maximum of 1.8W. We wanted to see what the impact was. We tested both a direct attach 2.5Gbps connection using CAT5e near the edge of the 100-meter maximum run length. We also tested the solution on a short connection to the switch using CAT6. We measured the impact on an Intel Atom C3558 server because that platform has relatively stable clock speeds and a low platform power base so we could see the impact measured at the wall.
- TEG-25GECTX to TEG-25GECTX 300 feet / 91.44 meters: 1.9W
- TEG-25GECTX to Switch 10 feet / 3.05 meters: 1.3W
Let us take a step back here. Under 2W is a margin of error for higher-end systems. For lower-end systems it is noticeable but likely has little to no impact. If you can use the performance, then this is a very minor performance delta.
At STH, we test up to dual port Mellanox ConnectX-5 VPI 100GbE adapters which makes 2.5Gbase-T speeds relatively mundane at a macro level. At the same time, the 2.5GbE TRENDnet TEG-25GECTX is an important milestone. One can get 2.5GbE speeds at a low cost, low power consumption, and in an easy-to-integrate PCIe 2.0 x1 adapter. With the ability to do this over 100m (we tested only to 91.44m but it is 100m on the spec sheet) on CAT5e, one can re-use existing wiring and get a greater than 2x performance upgrade.
At this point, 1GbE speeds are simply too slow for file transfers. 2.5GbE more closely matches modern hard drive speeds although one needs to move to 25GbE to match modern PCIe Gen3 x4 NVMe SSD speeds. At 1GbE, even modern hard drives are bottlenecked in terms of sequential transfer performance. It is time to upgrade.
We wish out-of-the-box experiences were all like Windows 10. The setup there was as easy as can be. Linux was only slightly harder but that will change with Ubuntu 20.04 LTS next year and that will no longer be a consideration.
If you want to get a 2.5GbE adapter for a workstation or a server, then the TEG-25GECTX is an easy answer. In the next year, we will see other options on the market with NICs like the Intel i225 instead of the Realtek chips, but for now, this is exceedingly easy.