Home Forums Peripherals & Multimedia Peripherals toasty thunderbolt

I did my first serious thunderbolt transfer yesterday and was surprised by how warm the connector ends on the cable got. You could definitely tell there was something going on in there.

I also discovered that Apple's FW800/TB adapter is bi-directional. This is uncommon for active adapters. I can use it to attach a macbook pro in target model to a powerbook g4 via fw/tb adapter and fw800 cable (treating the TB end as the peripheral end of the adapter) as well as to connect to a fw external HDD from a macbook air via it's TB port. (treating the FW end as the peripheral end of the adapter)

Did you find TB to be as fast as it's hype says it is?

I don't have anything nearly fast enough to test it with.

I would have to get a pair of mac pros together with 10k drives. testing with a 2.5" 5400 on either end would be pointless.

I realize that you couldn't begin feel TB's full impact with 2/2.5" x 5400, but shouldn't you at least be able to get an idea?

Apple has upgraded its entire line with TB, much of it to the exclusion of FW, so shouldn't its benefits be apparent across the board?

the last serious tests I did were with esata on my prior mbp, the last to have an expresscard slot. The drive I initially tested with maxed at 89MB/sec to /dev/null over esata, and I didn't understand why it was barely faster than FW800. So I retested with it installed internally in a mac pro, and got the same speed. I then looked up the spec on the hard drive, and that was it's top speed. So the drives were the limiting factor, not the protocol. That was a slower 3.5". 2.5" are slower than 3.5 on the average. So I would expect almost any laptop drive to be slower than thunderbolt.

FWIW I have a Thunderbolt monitor and the single TB connector carries the display, a FaceTime camera, a Firewire 800 port, and three USB 2.0 ports. With an external HD daisy chained with a Lightscribe optical drive on the FW800 port, a bus powered Blueray optical drive on one of the USB ports, and a couple of low speed devices on the other two USB ports. The TB connection seems to be fully capable of supporting all of these ports at full speed in addition to the Display and HD camera. I have not noticed any throughput limitations on the Thunderbolt connection, but your question made me curious to see if I could detect any throughput destruction through the TB connection.

The test I was able to come up with on short notice was to run a Drive Genius bench test on the external FW800 drive while it is connected to the FW800 port on the TB monitor and while it is connected to the FW800 port on the Mac mini. There was no difference, significant or otherwise, in the results of the two test runs. Of course, this could easily be explained if, the Mac mini could not drive the test data fast enough to reach the TB and/or FW800 limits or the speed of the external drive itself was the limiting factor. In either case, however, the Thunderbolt connection does not appear to have been a limiting factor even though it was carrying the display data as well as the FW800 data. Although the three USB 2.0 ports connected via Thunderbolt were active, their data throughput during the test was negligible.

My conclusion: Thunderbolt speed/bandwidth is VERY impressive and it is a major step up from Firewire 800 not to mention USB 3.0.

After reading V1's comment about drive speeds I should note the external drive I used is a 3.5" 7,000 rpm drive in an OWC enclosure, so it is a reasonably fast drive.

FW800 will be the limiting factor in your test, it's capable of at most 79MB/sec. the slowest desktop drive I have does 89MB/sec. The moderately faster one can manage 160MB/sec connected internally on sata. A good 10k drive would at least be needed. So firewire is completely inadequate for this test.

http://vftp.net/virtual1/temp/mfif/tb.jpg

(the IMG tag appears to be broken and THEN some, try it)

If that graph is correct, no single hard drive would be anywhere near maxing, not even an SSD - a high performance raid would be required to hit its limit.

Then cometh USB 3.0 "double", which is supposed to beat thunderbolt: http://ces.cnet.com/8301-34437_1-57562283/double-speed-usb-3.0-to-arrive-next-year/

But them you have to ask yourself... WHY? This is like having tires on your car rated 300mph. Almost no one will be able to use this, at least not for awhile.

Comparisons: http://news.cnet.com/8301-1001_3-57452785-92/thunderbolt-vs-usb-hdmi-pcie-cable-how-does-it-compare/

If USB3 can go double speed without requiring expensive transceivers at each end of the cable, it will KILL thunderbolt.