If you look at simple stats on buffer to platter transfer rates on hard drives, a typical rate is 780Mbs, and for USB its 480Mbs. I'm not convinced this reflects real world performance.

Lets say you have an external SATA II drive that has both SATA II and USB 2.0 connectors. Let's say you hook up the drive to your external SATA II port and do an RAR file transfer of 1 GB to your internal hardrive, and then you repeat the transfer using USB 2.0.

Does anyone know the REAL difference in speed you will see between the USB 2.0 and SATA II connections using the above test methods?

A friend of mine who thinks he knows it all (Masters in CS) says that the speed difference is negligible. As far as stats go, and stats alone, he is wrong-- 480 Mbps (USB 2.0) vs 780Mbs 7200 RPM SATA 150 HD transfer rates. But I'm wondering if he is more right when comparing real world testing parameters.

Thanks--

SATAII will be clearly faster if you timed both.

One only has to look at the data rate chart to see at the beggining where 480Mb/s is clearly the bottleneck.

The 480Mb/s for USB2.0 is not pour DATA. There is control packet as well as data sent.

My USB2.0 drives goes at about 25 MBytes/s. Far from my SATA hdd that goes at about 60 some Mbytes/s.

Hey Wusy, good to see you are still around.

Thanks to both of you for this information.

Do either of you know where I can get white paper information on this speed real world speed difference? I want to force feed this guy who has his Masters in CS the RAW data on his inaccurate know it all information. I'm going to wait until we're all around in a meeting and let everyone see how fucked up this prick really is. He likes to hold his knowledge above everyone's head like were all dumb asses. This time he's gonna get a mouth full.

Any links to tests etc also would be great.

Pat have you timed this using an external HD as I suggest in my initial?

I really want to take this asswipe to task on this, so I really need hard core evidence that he is wrong.

I mean the real world test would be as I've described it above, since we were talking about external HDs and I was wanting an enclosure that would mount a SATA II 3.5 drive and had both USB 2 and SATA II capabilities TO the computer. He said "Why, USB 2 is just about as fast at SATA II." So we're talking about real world transfer rates here from an internal BARE drive mounted externally enclosed in a external bare drive conversion kit (SATA to USB or SATA combo). I'm sure you both know what I'm talking about.

As a general bench mark, if you were transfering 1 GB of iinformation, what would the time difference be between USB and SATA II given the above parameters?

Normally I'd do this, but I'm busy today...

Look at some of THG's past (2004 I think) articles on USB and Firewire enclosures/ext HDD.
They have the Winbench99 graph of the same HDD being used on IDE, USB2.0 and Firewire.

Yeah that's just what I want. I need it in writing froma trusted source. Thanks man.

I have 2 hdd in external enclosure (WD120 Gigs and Maxtor 200gigs) and they run as fast as USB allow.. between 22 and 25 MBytes /s.

You can seatch for motherboard review, on anandtech, for review of the a8r-mvp and some nforce4 motherboard. they test the speed of usb and sata so you'll have the proof you need.

but anyway.. usb2.0 run at 480Mbits/seconds whlie sata2 specs allow for 3.0 Gigabits/seconds, about 6 time faster interface speed..

Pat, those specs can't be compared like that. We're talking about a real world test where you take information off of a hard drive and transfer that same information to another hard drive. It other words, overall transfer rate, or the time it takes to write a file(s) using USB and then compared that to SATA II, all other things being equal.

I've searched like 2 hours last night and couldn't find anything like that. I found something close, but no real tests like that.

Any links would be appreciated.

That is the best I found. It's between USB2 and Firewire on the same enclosure.
If you were to strip the drive out and put it on IDE it would be even faster.

If your friend still isn't convinced, then suggest him to get Firewire800 instead.

USB is quick, Firewire quicker, IDE Fast, SATA Faster, SATAII Faster still...

The exact test you are talking about is done with this enclosure. It is made by Vantec. I just bought one from zipzoomfly. I expect it early next week along with a Seagate 250GB sata drive.

Anthony


http://www.bigbruin.com/reviews05/ [...] ns3&file=1

Thanks nfor the link Antony. However, those are only burst speeds, which can be no doubt misleading when you are talking about the METHOD ABOVE!!!!!!!!!<--Real Time Transfer Rate. You would think someone, uh like Tom's, would do that test.

Yeah that will definitely convince a person who has their Masters Degree in CS from University of St. Luois.

listen.. I'm nothome righ now but I c a assure you that moving a file to my usb enclosure take 3-4 more time than moving the same file between 2 sata or pata hdd..

Wusy,

Yeah I found that too. Too bad they didn't compare eSATA also, but I didn't check the date--perhaps it wasn't available. What I'll need to do is find the same drive tested using eSATA then find the same drive and enclosure on this essay and comapre them--however that will be near impossible unless I can find teh exact same drive, enclosure, and test program+platform.

My friend isn't going to buy anything, I am. He simply was telling me I was an idiot for wanting a eSATA connection instead of (or now with) USB 2.0, since he thinks USB 2.0 compared to eSATA is "not much faster."

This is just a war of EGO, and his is too big and he is wrong. I just want to chop him down by showing him incontrovertible evidence that he is WRONG. Plus, and I will make this coment to him, for someone in the IT business and with a Master Degree in CS, he better get his $hit together. I mean if he tells his clients that USB is almost as fast as SATA II, he is grossly misleading them.

And since this discussion we had, he said he doesn't want to talk to me about technical things anymore becsaue I don't know what I'm talking about. I've pretty much written him off as any type of friend, but revenge in this way is indeed sweet. I know you feel the same way, so let's keep looking bro.

I use eSATA, but that the weird hybrid version made by Highpoint not the proper eSATA with pure SATA interface.
IDE->SATA->IDE for Highpoint's eSATA :? (Lots of converter chips)

Either way it's diffinitely faster putting HDD on a proper ATA interface than on external interface like USB2.0 with the exception of Firewire800.

I'm pretty sure THG had one with IDE included as well...

Here is another review of the Vantec Esata unit. Is this speed Real time transfer rate?

http://www.3dgameman.com/vr/vantec [...] ew_03.html


Anthony

Easy way to settle this is the two of you pick out a USB SATA Combo Enclosure and a hard drive. Put agreed upon data on it and then time the 2 transfers with a stop wacth. The loser pays and the winner has a new external hard drive.

There's one major obstacle with eSATA, you need to find a computer with a break-out eSATA port. Not something you find on everyday computer compared to USB2.0

Out of all external storages I prefer Firewire over the rest.
Faster than USB2.0 in real life tests, no need external power.