ATA and sustained transfer rates

[VideoTechMan]

A question, thought to see if i can get some feedback....all IDE hard drives whether they are 5400 RPM or 7200RPM most ads and the descriptions say they can transfer to 100MB/sec, or for the ATA133 hard drives, to sustain 133MB/sec. Now what I want to know is.....do these drives actually sustain these speeds as they have been labled to? I have a program that I downloaded from Canopus's tools site that measures the sustained transfer rates of the hard drives, and the max I have been able to attain from both of mine was about 50MB/sec, way below the spec the drive has. Since all DV capture is at a fixed 3.6MB/sec, I would be pretty sure that 50MB would be more than enough to capture without dropping a single frame.

Check out my new computer specs...I finished building my new system over this past weekend and right now I am doing a test capture of a VHS tape using the passthrough from my DV deck to the computer. So far I have done about 10 minutes of capture and not a single frame has been dropped. Im mainly checking to be sure theres no A/V sync loss.....but since the pass through is going thru the Panasonic DV deck, which is a professional deck and costed me 2 arms and a leg for, it should work just fine. Looks like I wont need the ADVC-100 after all.

So any thoughts about the ATA spec and ways to improve it if possible? Thanks for your insight.

VTM

[sterno]

They market the drives on the theoretical maximum transfer rate for the interface - usually 66/100/133MB these days. The physical mechanisms can not transfer data that fast. The only time you get that speed is when it's going directly from the drive's cache, which is why increasing the cache to 8MB made a difference.

[rallynavvie]

Where is this utility you found? I'd like to run all my hard drives (of which I have many) to see what kind of speeds I'm seeing for transfers. I wish I had a hard drive benchmarking utility, but then I guess I've never really looked for one.

[mrtristan]

That's the burst speed of the drives. ATA100 drives are theoretically capable of 100MB/s bursts, while ATA133 drives can do 133MB/s. Usually, the sustained data rate is closer to 30-60MB/s. That depends on the drive's RPM, buffer size, build quality, and motherboard controller. 50MB/s sustained is pretty good.

[VideoTechMan]

Where is this utility you found? I'd like to run all my hard drives (of which I have many) to see what kind of speeds I'm seeing for transfers. I wish I had a hard drive benchmarking utility, but then I guess I've never really looked for one.

Rally you can go to www.canopus.com and you will have to register to their site first but once you do, you click under support and go to Utility downloads, and its called EZDV Test. Its a very small prog but does wonders when it comes to measuring hard drive sustained speeds, and it also tells a little about your system specs as well. If you need help let me know.

I completed the 20-minute VHS test capture last night, captured an cartoon episode of Inspector Gadget from one of my older tapes I have, and did very well without a glitch and not dropped a single frame. I think that did quite well

VTM