Onboard NIC vs. PCI NIC

[dragontales]

Seeing that most motherboards on the market today has onboard NIC and that pci NICs are becoming obsolete....

what are the advantages and disadvantages of both?

 

[teststrips]

I switched to gigabit in my house about 3 months ago... I had to install PCI nics in my older computers b/c the built-in nics were only 10/100. One of my comptuers was new enough to have built-in gigabit.

1 - a PCI NIC with a good chipset would use less CPU power (but CPUs are so fast now, it really doesn't matter).
2 - the Killer NIC is supposed to help with gaming performance.
3- You could need multiple PCI nics if you wanted to make an X86 based router/switch.

I guess I'm done coming up with reasons you MIGHT want to get a PCI nic.

 

[Madwand]

These days, on-board NICs, esp. on-board gigabit NICs are generally good enough, so you don't need to spend more on an add-on NIC.

PCI is obsolete, esp. for components such as gigabit NICs and matching storage controllers -- gigabit can exceed PCI bandwidth by itself. The real alternative for high bandwidth needs is PCIe. (PCI-X is another alternative, but only suited to server hardware, and even there it's being replaced by PCIe.)

Some on-board gigabit NICs use the PCI bus. These should be avoided for the same reason that add-on PCI GbE NICs should be avoided: (1) The PCI bus can be a bandwidth bottleneck, esp. when shared with other high bandwidth devices. (2) The PCI chipsets are older, and sometimes (commonly, but not always) better-performing chipsets are available in PCIe format (e.g. Marvell).

However, even a cheap/slow PCI gigabit NIC can be a huge improvement over standard 100 Mb/s for local file transfers (assuming the obvious requirements), and such setups are often limited by hard drive and other bottlenecks, so in many cases there's no practical difference between a PCI-based gigabit NIC and a higher-end PCIe or on-board gigabit NIC.

One specific reason for an add-on gigabit NIC is the support for jumbo frames. Unfortunately, many on-board gigabit implementations do not support jumbo frames (even Intel!). This is another feature that may or may not give benefits depending on the circumstances. Of course it's generally better to have the option.

 

[YeOldeStonecat]

As long as the chipset of the NIC is decent..performance wise there is pretty much no gain or loss.

Older motherboards..just because it's onboard..doens't mean it's not a PCI based card...it's still using the PCI bus..it's just..built in.

Newer motherboards..they're often PCIe, or somehow tied with with the chipset (nVidia for example)...and bus throughput is fantastic.

So a native advantage is performance....plus you know since it was designed into the board, it will have optimal settings such as IRQ...so no conflicts/incompatibilities (think back to the crappy Via chipset with the PCI bus latency issues)

One disadvantage that I've seen...sometimes an onboard NIC will cook the motherboard if a power surge comes in through the ethernet. Yes a PCI NIC can pass that through also..but I've also seen PCI NICs take the full brunt..cooking themselves..yet the mobo stays fine. Simply replace NIC.