Slow-ish FW800 Transfer Speed

[smeg36]

I purchased a FW800 enclosure for my Seagate 500GB 5400rpm HD. I just got a 2010 13" MBP. I was previously using a 2006 MBP with an ExpressCard slot, and had this hard drive connected over eSATA. According to TomsHardware the max sustained write speed of this drive is around 65MB/s, which is what I was getting over eSATA.

So I got the FW800 enclosure now that I can't use eSATA with the thought that I'd be getting the same 65MB/s that this drive is capable of. FW800 should be able to handle up to 100MB/s. But I'm only getting around 40MB/s, closer to what I should be getting if I was using FW400. Any ideas about why I lost 25MB/s in transfer speed?

 

[spinnerlys]

Maybe you have an enclosure with a bad chipset, but even though Firewire 800 has a theoretical throughput of 800 Mb/s (100MB/s), in real life it only has 65 to 75 MB/s, as even USB 2.0 with 480 Mb/s has no real life speed of 60 MB/s.

My FW800 speeds vary from time to time, depending on file count. The more files I have, the slower the speed, but with big 10+ GB files I can have 65 to 75 MB/s via FW800 or 100 MB/s and more via eSATA.

 

[smeg36]

Is there any way to test that, or should I just get it replaced while I can? There aren't a whole lot of FW800 options out there for an enclosure. I got this one as an open box from Amazon Warehouse. Maybe that's why it was returned.

 

[spinnerlys]

Is there any way to test that, or should I just get it replaced while I can? There aren't a whole lot of FW800 options out there for an enclosure. I got this one as an open box from Amazon Warehouse. Maybe that's why it was returned.

You could try to copy one large file and see how the speeds go then. Btw, what file system is the external HDD using?

PS: If you don't have one large file (10GB +), you could use AJA System Test for that.

 

[smeg36]

My drive has two partitions, a HSF+ and a FAT32. Most of the time I transfer files to the FAT32 partition to play on my PS3. That's the partition that gets around 40MB/s, usually transferring 3-4GB files. I just tried transferring a 8GB file to the HSF+ partition and got 50MB/s consistently. Using the same file, drive, and partition over USB got me 27MB/s.

I put the drive in another USB enclosure I have I did the same 8GB file transfer to the HSF+ parititon and got 30MB/s.