I’ve always heard, going back to the 1990s, that you should go with an Intel NIC vs Realtek or another low-tier brand. But why? “Because the most expensive one is obviously the best,” and “because I like Intel CPUs” aren’t good answers.
I often noted the Intel advocates weren’t ever spending their own money. It’s easy to say the more expensive solution is better when someone else pays the bill. So let’s try to take a look at this objectively and quantify the differences between the two.
Intel NIC vs Realtek: Cost
Cost-wise, you just can’t compete with a Realtek NIC that costs $3.55, shipped. And when you buy a motherboard, odds are there’s a Realtek chipset on the board unless it’s an enthusiast board. You never see that cost, but it’s also non-optional. Name-brand Realtek cards cost closer to $15, especially if you buy at retail. Most cards you find in retail stores under brands like D-Link, Netgear, Linksys, and TP-Link have Realtek chips on them.
You can get a surplus Intel card for a lot less than retail, but you’ll still pay more than $4 for it. Intel cards start at around $40 new. Used Intel cards typically sell for around $15.
Intel NIC vs Realtek: Stability
You shouldn’t think of all Realteks as equal. When you look at the reviews sections on retailers’ pages, you can always find a small number of people who had trouble getting generic Realtek cards working, in spite of the people who say it’s the most common chipset in the world, it’ll just work.
They’re right, it is the most common NIC chipset in the world, and more often than not, it does just work. But that doesn’t help you when someone looks at the Realtek reference design, sees a way to make the card cheaper, and it causes problems in rare circumstances and your system is the rare circumstance.
If you really want something that just works, Intel is the safer bet.
Intel NIC vs Realtek: Throughput
Intel NICs will generally give, at minimum 5% greater throughput than a Realtek. Under extreme circumstances the difference can be much greater. The difference is greater on large transfers than on small transfers. If you want your NIC to saturate its link as much as possible, go with Intel.
Intel NIC vs Realtek: CPU utilization
During transfers on my Apache server, I find my Intel NIC uses 10-20% less CPU power than my Realtek. I observed single requests with my Realtek card using 19 percent of one CPU, while my Intel card used 8 percent. Heavy loads that would take my CPU above 80 percent top out at 55 percent now. I use an Intel J1900 CPU. On rare occasions, someone will hammer my machine and drive CPU usage north of 90 percent. I’ll appreciate the Intel NIC if that happens again.
Both types of NIC have the ability to offload some TCP and UDP functions to the NIC, rather than using the CPU. These options work well on Intel cards, at least on desktop and laptop machines. They are buggy on Realtek.
Your results will vary based on your CPU, but the Intel cards always tax the CPU less. You can think of a Realtek card like the Winmodems of old, and the Intel card like the costlier but better US Robotics hardware modems.
Intel NIC vs Realtek: Driver and OS support
No matter what operating system you want to run, you can pretty much count on stable, mature Intel drivers. Intel drivers work well in Windows, Linux, Mac OS, all of the BSD derivatives, and popular FreeBSD-based appliances like FreeNAS and pfSense. For the FreeBSD-based appliances, enthusiasts recommend Intel NICs, for several reasons. The Intel drivers work much more reliably and don’t require any significant tinkering to get working, and they provide better performance.
I’ve never had trouble getting the Realtek networking built into name-brand hardware working in Windows or Linux, but I haven’t done any experimenting with the sub-$4 cheapies. Horror stories about Realtek cards with FreeNAS and pfSense aren’t hard to find.
If you stick with name-brand Realtek cards, you’re less likely to run into issues, but you also lose some of the cost differential that way. A D-Link NIC costs $13-$15 and I can usually pick up a used Intel card for around $15. Granted, it’s used vs. new, but I’d rather have the used Intel card.
Intel NIC vs Realtek: Longevity
Realistically speaking, I typically can get many years out of any network card. I’ve seen fewer failed Intel cards than others, but the number isn’t zero. The Intel card I found didn’t fail completely, but couldn’t communicate at any faster than 10 megabits. That card was in a junk pile. Its crippled speed is probably why. Usually when cards fail to communicate at high speed it’s the cable, but sometimes it can be the card.
I don’t have a statistically significant sample size of any type of network chipset, but when I was managing a decent-sized network, I never had an Intel card fail on me. I’ve only had one Realtek card fail on me at home, which is a higher percentage than Intel, but I wouldn’t call my home network of a dozen or so machines a statistically significant sample.
For this reason I won’t assign an advantage, but I’ll lean toward Intel.
Would I ever buy a Realtek NIC?
So after all this Realtek bashing, I’m sure you’re asking if I’d ever use one. I have, and sometimes do. For modest workloads on a home PC they’re fine. I’ve even seen them survive in business environments. I have a hard time justifying putting a $40 network card on a $50 motherboard.
But once secondhand Intel network cards got cheap, I started buying them. As I swap motherboards, I’ll take them with me. But if I could only afford a small number of cards, I’d put them in my servers, and keep Realteks in my desktops.
PCI vs PCI Express (PCIe)
The PCI bus runs at 33 MHz, which was fast for the mid 1990s, but not so much today. You’ll get better performance if your system has PCI Express slots available. If PCI is all you have, the difference between an Intel NIC vs Realtek can be even more pronounced, since the CPU can’t push data to the NIC as quickly.
PCI Express is the future, so if you can get PCIe cards, do it, even if it means paying a little more.
Managing the cost
Keep in mind you can keep an Intel NIC for years and take it with you when you upgrade. Look for a used Intel NIC, particularly a rebranded IBM, HP, or Dell NIC, to save costs. Dual-port NICs are easier to find, but single-port NICs sell for around $15 when you can find them. They’re easier to find during the week while inventories are getting refreshed than on the weekend. Dual-port NICs sell for closer to $25. If you need two ports, that’s a bargain.
Business-class machines often have Intel NICs in them. If you’re shopping for an off-lease business PC, it pays to look up what kind of networking they include. By switching models, you may be able to get Intel networking at little or no additional cost.