Re: [gentoo-user] Looking for PCI-X external SATA controller
On Thu, 2008-02-14 at 23:12 -0600, Dale wrote: Neil Walker wrote: Kevin O'Gorman wrote: I can find a lot of cards that are almost what I want. But I have an external drive, and a PCI-X motherboard. Not internal, and not PCI-E. Anybody know of such a beast A quick Google led to this: http://www.newegg.com/Product/Product.aspx?Item=N82E16816124003 Be lucky, Neil Dale makes a note of this. Questions: If I buy this card and a SATA hard drive, will I notice faster transfer speed on the drive or will the PCI bus limit it somehow? I currently get 40 to 50 MBs/sec on my IDE drives. Would this setup be any faster? Thanks Dale :-) :-) Short answer: no. Long answer: You'd need to flood your PCI-bus with data to see any drop in speed. Ways to do it? Buy four disks and build a RAID1 using Linux device mapper. Since the data sent to the devices is not replicated on a RAID-controller (e.g. after transfer through PCI) but in software, you'd send four times the amount of data through your poor old PCI-bus. signature.asc Description: This is a digitally signed message part
Re: [gentoo-user] Looking for PCI-X external SATA controller
On 15 Feb 2008, at 05:12, Dale wrote: Dale makes a note of this. Questions: If I buy this card and a SATA hard drive, will I notice faster transfer speed on the drive or will the PCI bus limit it somehow? I currently get 40 to 50 MBs/ sec on my IDE drives. Would this setup be any faster? If you want faster throughput then onboard controllers or PCI-express (PCI-e) are the way to go. I'm not sure how the bandwidth of regular old PCI compares to (i.e. limits) that of an SATA harddrive, but you can come across PCI's performance limitations if using a RAID array. PCI-express has _signifcantly_ more capacity than regular old PCI - I read recently that regular old PCI may be unable to keep up with a gigabit network card that onboard gigbit network ports are faster. I tend to think of PCI-X just as long PCI or only-a-bit-faster-than PCI. It might be (say?) double the speed of short PCI, but it doesn't match PCI-e's several-times (?) performance. PCI-X may be useful when trying to get the best performance out of an older motherboard, or if you're trying to save money by picking up an expensive hardware-RAID card cheaper secondhand, but I would try to avoid investing too much money in it until you've done the maths - a new motherboard / CPU / RAM might even be cheaper faster. Stroller. -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
Stroller wrote: On 15 Feb 2008, at 05:12, Dale wrote: Dale makes a note of this. Questions: If I buy this card and a SATA hard drive, will I notice faster transfer speed on the drive or will the PCI bus limit it somehow? I currently get 40 to 50 MBs/sec on my IDE drives. Would this setup be any faster? If you want faster throughput then onboard controllers or PCI-express (PCI-e) are the way to go. I'm not sure how the bandwidth of regular old PCI compares to (i.e. limits) that of an SATA harddrive, but you can come across PCI's performance limitations if using a RAID array. PCI-express has _signifcantly_ more capacity than regular old PCI - I read recently that regular old PCI may be unable to keep up with a gigabit network card that onboard gigbit network ports are faster. I tend to think of PCI-X just as long PCI or only-a-bit-faster-than PCI. It might be (say?) double the speed of short PCI, but it doesn't match PCI-e's several-times (?) performance. PCI-X may be useful when trying to get the best performance out of an older motherboard, or if you're trying to save money by picking up an expensive hardware-RAID card cheaper secondhand, but I would try to avoid investing too much money in it until you've done the maths - a new motherboard / CPU / RAM might even be cheaper faster. Stroller. So basically I need to build a new rig with newer stuff? I have a old Abit NF7-2.0 mobo right now. I want to build a rig with dual CPUs and all the new stuff. Got to save up some serious cash first tho. Being disabled makes that take a little time. Thanks for the info. Dale :-) :-) :-) -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
On Freitag, 15. Februar 2008, Stroller wrote: PCI-express has _signifcantly_ more capacity than regular old PCI - I read recently that regular old PCI may be unable to keep up with a gigabit network card that onboard gigbit network ports are faster. PCI = 133mb/sec theoretical. 100mb with a good chipset (ie not nforce). PCIE = 250mb/sec theoretical I tend to think of PCI-X just as long PCI or only-a-bit-faster-than PCI. you think wrong. It might be (say?) double the speed of short PCI, but it doesn't match PCI-e's several-times (?) performance. PCI-X is A LOT faster than PCI, faster than PCIE 1x, 2x http://en.wikipedia.org/wiki/PCI-X PCI-X 1.0 = 1GB/sec PCI-X 2 = 2GB/sec -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
Volker Armin Hemmann wrote: PCI = 133mb/sec theoretical. 100mb with a good chipset (ie not nforce). PCIE = 250mb/sec theoretical I think 64-bit 66Mhz PCI will actually do 526Mb/s theoretical maximum ... I can achieve 220Mb/s real I/O bandwidth (4 disk array) on my gear here. (old Supermicro P4TDER). Cheers Mark -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
On 15 Feb 2008, at 15:57, Volker Armin Hemmann wrote: ... I tend to think of PCI-X just as long PCI or only-a-bit-faster-than PCI. you think wrong. ... PCI-X is A LOT faster than PCI, faster than PCIE 1x, 2x Ooops. Hi Volker, My apologies for posting misleadingly my thanks to you for correcting my embarrassingly-incorrect understanding. I think I must've misread 64-bit PCI for PCI-X on this table when I was doing my homework a few weeks ago: http://en.wikipedia.org/wiki/List_of_device_bandwidths#Computer_buses Looking at the 3ware / AMCC high-end RAID controller cards (which are excellently supported under Linux) I find that the manufacturer seems to currently be abandoning PCI-X for PCIe. Why is this, in the case? I also read that: ... while standard PCI-X (133 MHz 64 bit) and PCIe x4 have roughly the same data transfer rate, PCIe x4 will give better performance if multiple device pairs are communicating simultaneously or if communication within a single device pair is bidirectional. http://en.wikipedia.org/wiki/PCI_Express#Overview I'd guess that few motherboards have many PCIe x4 and x8 slots, and - apart from graphics cards - few devices utilise them fully. Don't you think, however, that this is likely to become a lot more common in the next couple of years? Are manufacturers currently announcing brand new products based on PCI-X? Stroller. -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
I wrote: I think 64-bit 66Mhz PCI will actually do 526Mb/s theoretical maximum ... I can achieve 220Mb/s real I/O bandwidth (4 disk array) on my gear here. (old Supermicro P4TDER). Actually, doing the calculation properly gets 508 MB/s (532 MB/s is often quoted, but that is using 1000 instead of 1024 bytes to the Mbyte). For the interested: 32-bit 33.33 Mhz PCI bus can transfer 32*33.33*100/(8*1024*1024) = 127 MB/s 32-bit 66.66 MHz PCI bus can transfer 32*66.66*100/(8*1024*1024) = 254 MB/s 64-bit 66.66 MHz PCI bus can transfer (skip obvious calc now) 508 MB/s Clearly PCI-X with its 100, 133.33 and 266.66 MHz variants will get you 763, 1017 and 2034 MB/s. Cheers Mark P.S : also typo'ed the machine - is a P3TDER... -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
Kevin O'Gorman wrote: I can find a lot of cards that are almost what I want. But I have an external drive, and a PCI-X motherboard. Not internal, and not PCI-E. Anybody know of such a beast A quick Google led to this: http://www.newegg.com/Product/Product.aspx?Item=N82E16816124003 Be lucky, Neil -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
On Thursday 14 February 2008 06:08:23 pm Neil Walker wrote: Kevin O'Gorman wrote: I can find a lot of cards that are almost what I want. But I have an external drive, and a PCI-X motherboard. Not internal, and not PCI-E. Anybody know of such a beast A quick Google led to this: http://www.newegg.com/Product/Product.aspx?Item=N82E16816124003 Be lucky, Neil I'm confused... what is the diff between pi-x pci-e and pci? The card that Neil pointed to is a PCI card. Is that what he wanted? -- From the Desk of: Jerome D. McBride -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
On Freitag, 15. Februar 2008, Jerry McBride wrote: I'm confused... what is the diff between pi-x pci-e and pci? The card that Neil pointed to is a PCI card. Is that what he wanted? pci is a parallel bus. 32bit, 33mhz pci-x is an 64bit, 66mhz enhancement of the pci bus - backwards compatible. If you are lucky. pci-e is a serial point-to-point interface. Not compatible. -- gentoo-user@lists.gentoo.org mailing list
Re: [gentoo-user] Looking for PCI-X external SATA controller
Neil Walker wrote: Kevin O'Gorman wrote: I can find a lot of cards that are almost what I want. But I have an external drive, and a PCI-X motherboard. Not internal, and not PCI-E. Anybody know of such a beast A quick Google led to this: http://www.newegg.com/Product/Product.aspx?Item=N82E16816124003 Be lucky, Neil Dale makes a note of this. Questions: If I buy this card and a SATA hard drive, will I notice faster transfer speed on the drive or will the PCI bus limit it somehow? I currently get 40 to 50 MBs/sec on my IDE drives. Would this setup be any faster? Thanks Dale :-) :-) -- gentoo-user@lists.gentoo.org mailing list
