Dedicated PCI cards = less CPU usage?
 

I've been looking for an answer to this question for a while. Does installing dedicated PCI cards reduce CPU usage? I'm talking about like a NIC, sound card, or PCI to USB cards. I know for certain that sound cards can help decrease CPU load by processing EAX and fancy stuff like that, but what about other types?

I know I have read about how the new "Killer" NIC actually does offload CPU tasks to itself for better performance. As to other NIC's, I don't know.

You are dead on about the PCI soundcards. Although it is cheaper and more affordable to use on-board (Motherboard) sound, it is more CPU tasking than the alternative.

As to PCI-USB ports, I don't think so.

It depends, actually. The nForce2 onboard-soundchip, "Soundstorm" in fact had lower CPU usage than the best PCI cards at that time, including the entire range of Creative Audigy cards. It also featured Dolby Digital 5.1 realtime hardware encoding for the first time ever on a PC platform.

That and the integrated Firewire ports are why I bought an older nForce 2 mobo for my old PC after my MSI one died. Love Soundstorm, and I wish they'd kept developing it.

Ah well.

Sorry I didnt mention the one exception that is long since out of production :rolleyes:. But yes you are right Soundstorm does kick. And that was so stupid to quit developing it.

Soundstorm is not the only exception, though. The new HDA standard also introduces very low CPU usage for sound processing, lower than many PCI solutions on the market. Besides, you will not notice the difference in speed between 5% CPU usage for onboard sound (worst) and 3% CPU usage for PCI (best) on a fairly modern system.

Some onboard NICs also come with a dedicated chip, most notably the Marvell Yukon series (Gigabit), using virtually no CPU time, while I've seen budget PCI cards (especially Netgear) use up to 10% and spiking like crazy under heavy traffic.

The statement that PCI cards generally have lower CPU usage than their onboard competitors does not apply anymore.

In an absolute sense, yes. All onboard components use CPU time.

In a practical sense, the only onboard component intensive enough to degrade performance is a sound card. You won't notice using an onboard NIC versus a PCI one. And all a PCI HD controller will do is bottleneck your PCI bus.

Using up CPU cycles isn't as important as using bus bandwidth these days. Having a bunch of dedicated PCI cards in one system is a very bad idea because they are all sharing a 133MB/sec bus. Hell, just a Gigabit Ethernet card running at capacity will eat up most of the bus bandwidth. Forget putting anything else on the bus if you are using a SATA PCI card as well. SATA-II can't even run on a PCI card, those require a 64-bit PCI slot (PCIe or PCI-X).

For the most part, onboard stuff is the way to go these days. A lot of decent chipsets have dedicated chips for IDE/SATA processing, network/USB/various port processing, sound processing, etc. Not only that but most if not all of these components also have a dedicated bus to memory and the CPU which keeps all of the data off of the limited PCI bus.

I thought I might post that "Killer NIC" in here for LOL.

http://www.killernic.com/KillerNic/

$280 for a couple of percent better frame rates and ping times...I wonder how many of those they'll sell? Even nutty gamers have to have some sort of spending limits...don't they?

-looks up pricing for Crossfire X1900s and Core 2 Extreme processors-

On second though, maybe we should all buy some stock in these guys.

I think everyone else has summed it up fairly nicely, but there's not much reason to buy cheap SATA, USB, network, or sound cards. You might get a bit of a boost in gaming performance and sound quality if you buy an Audigy or another higher-end sound card, and big fancy drive controller cards offer up full RAID functions, but that's really about it.