ATA100/133 Onboard Controller or ATA100/133 PCI Card Based Controller....Which is Better?

[GotSomethingCheaper?]

Hi guys,
Recently i have seen a couple of posts stating that using a PCI based controller rather than a onboard controller can provide better hard drive performance.
Is this true? I am considering purchasing a 80gb Maxtor ATA133 hd which comes with a free ATA133 (4 Channel) PCI controller card. I have an existing 80gb ATA100 that I also have.
I was wondering if any of you had comments, opinions, evidence for whether or not PCI card based controllers are better than onboard controllers.

Hope someone can fill us in, as many people out there may not be aware of this, especially with newer "high performance" systems.

 

[cholley]

i wouldnt think there would be a diffrence, but i can see an advantge to the card, (you get extra ports )
but the speed rating is the transfer between the head and buffer and not actual throughput so any diffrence in performance would be minimal if any, now consider is the pci bus faster or slower than the ide bus?

 

[WetWilly]

Theoretically an IDE controller chip should perform the same whether mounted on a PCI card or on the mobo, since the mobo mounted chip is using the PCI bus anyways - just not a PCI slot.

If you have spare PCI slots, I'd personally rather have the PCI card, since if your mobo dies you can still move your IDE/RAID drives to another rig pretty easily.

[Edit]
There is a difference, though, between PCI cards and the newer SIS/VIA southbridges where the IDE controller doesn't sit on the PCI bus. With VIA boards in particular, if the RAID latency patches aren't installed, the onboard VIA IDE will be faster than the PCI card IDE controller.

 

[Barrei]

I concur with wetwilly

 

[GotSomethingCheaper?]

I have a Soyo Dragon Plus VIA KT266a board... would that come under the "SIS/VIA southbridges" description... also would you have to install those even if your arent using a raid setup for those speed improvements?

 

[WetWilly]

would that come under the "SIS/VIA southbridges" description

Yes. VIA V-Link and SiS MuTIOL southbridges don't have the IDE controller directly connected to the PCI bus.

would you have to install those even if your arent using a raid setup

Not necessarily. If you're not having performance problems with the drives attached to the Promise (?) controller, don't worry about it. A few months back a German site did rather extensive benchmarking of IDE controllers and documented the VIA-PCI latency issues with IDE and SCSI RAID controllers. There was a latency patch posted over at VIAHardware, then VIA released a RAID Performance Patch which may have been integrated into one of the newer 4-in-1s. Haven't checked what's changed in the last few 4-in-1s myself. Regardless, the latency patches don't seem to hurt anything, so it may be worth a shot.

 

[GotSomethingCheaper?]

Ok thanks for all the help WetWilly.
Much appreciated.

 

[WetWilly]

No prob.