In a message From: David Elmo <[EMAIL PROTECTED]> writes: << > >> If you are going for full LVD performance you will need a SCSI card and >> ribbon cable that supports LVD without adapters. > > Without adaptors? My Seagate has an 80 pin connection and nothing else, so > it has to have some adaptor to get the 4 pin power surely? The LVD compliant > cards I have looked out for have 68 pin connectors. (True, I am running it > at the moment (in a test rig, lid off! for short periods of time) in SE mode > on an ATTO and it is faster than I have ever had. Look, before I pop off the > earth, I want to experience the full throttle of this however impractical>> > > Go to the ATTO support site and download ExpressPro-Tools it will benchmark > your drive's performance. In the LVD mode you should get a peak read of 48-52 > MB/S . At least that's what I got on my 7500 with a pair of 68 pin 7200 rpm 18 > GB WD HDD and the ATTO UL2D. The sustained rate was much lower. As I recall > around 17-18 MB read and 11-14 MB write. That was with all the proper cables > and > no adapters. Far better than the stock internal SCSI bus on the 7X00 PCI > Macs. You should see similar performance with your set up. > > OTOH, installing the same card in a G-4 Sawtooth (OS 9) with the same drives > and cables doubled the performance, IIRC. Anyway that where they are now. > --glen
[snip} So your experience without adaptors is not quite relevant to my situation. >> --------------- Yes, not relevant but something to consider. My understanding for full LVD performance requires a LVD supported SCSI card, a LVD supported drive and a LVD cable with active termination. Perhaps an adapter will suffice and not slow down the mix -- don't have that experience as you have pointed out?. ---------------- <<I can't yet run my LVD Seagate in LVD mode because I need the right card. I have done my own practical tests like transferring 600 MB of data from one partition to another or duplicating same with a stop watch. My Seagate on my ATTO in SE mode is impressive on this score and a treat is in store when I go LVD... >> ------------- This a good practical way to bench mark. Good to see you have a great improvement. I would be interested in the performance gain you get when you go to LVD. But then how will you know if you are actually in LVD or PE mode? The thing with software benchmark utilities it allows us to compare performance with our particular configurations. I don't own a stop watch and really don't want to buy one; yeah, I know I could just use a clock. Benchmark utilities can be downloaded free and while they do not give real world times they do give us a standard to compare performance. My reference to the G4 with all the same transplanted LVD hardware was just to show that 7x00 series PCI Mac do have data transfer limitations. This reference was not to belittle the usefulness of these machines. I still have plans for all the ones I own. Hey, I writing this on a 6100 which I still find to be useful. Keep us posted. I am really interested in your project. Peace --glen (digest mode) -- PCI-PowerMacs is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | -- Sonnet & PowerLogix Upgrades - start at $169 | & CDRWs on Sale! | Support Low End Mac <http://lowendmac.com/lists/support.html> PCI-PowerMacs list info: <http://lowendmac.com/lists/pci-powermacs.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[email protected]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive:<http://www.mail-archive.com/pci-powermacs%40mail.maclaunch.com/> iPod Accessories for Less at 1-800-iPOD.COM Fast Delivery, Low Price, Good Deal www.1800ipod.com
