Data Transfer speeds, pio dma udma firewire usb2 pc bus etc

[techAdmin]

There's a great table that has most of the different network/internal transfer speeds here.

Eat your geek hearts out, now you know.

[ The following numbers are all in bits per second, divide by 8 to get bytes per second ]

:: Code ::

Value       Units       Service
28.8    kbps    Plain Old Telephone System (POTS)
56    kbps    Switched 56
56    kbps    Switched Multimegabit Data Service (SMDS)
64    kbps    Integrated Services Digital Network (ISDN)
64    kbps    DS0
128    kbps    ISDN Dual Channel
230.4    kbps    LocalTalk
640    kbps    Asymmetric Digital Subscriber Line (ADSL) Upstream
1    Mbps    Cable Modem
1.544    Mbps    DS1/T1
2    Mbps    IEEE 802.11 wireless (2.4 GHz band)
2    Mbps    PCS Wireless
2    Mbps    ECP/EPP PC to PC Connection (Parallel Port)
2.048    Mbps    E1
3.33    Mbps    ATA Hard Drive PIO Mode 0
5.22    Mbps    ATA Hard Drive PIO Mode 1
6    Mbps    Asymmetric Digital Subscriber Line (ADSL) Downstream
6.312    Mbps    DS-2/T2
8.33    Mbps    ATA Hard Drive PIO Mode 2
8.448    Mbps    E2
10    Mbps    10Base-T Ethernet
11    Mbps    IEEE 802.11b wireless (2.4 GHz band)
11.11    Mbps    ATA Hard Drive PIO Mode 3
12    Mbps    Universal Serial Bus (USB)
16.67    Mbps    ATA Hard Drive PIO Mode 4
24    Mbps    U-NII Wireless
33    Mbps    Ultra DMA Hard Disk 33
34.368    Mbps    E3
40    Mbps    SCSI-1
40    Mbps    IEEE 802.11a wireless (5.6 GHz band)
44.736    Mbps    DS3/T3
51.84    Mbps    OC-1/STS-1 Synchronous Optical Network (SONET)
64    Mbps    16-bit ISA card (needs 2 clock cycles)
66    Mbps    Ultra DMA Hard Disk 66
80    Mbps    Fast SCSI
80    Mbps    PCMCIA Card (PC Card) 16 bit
100    Mbps    100Base-T Ethernet (Fast Ethernet)
100    Mbps    Ultra DMA Hard Disk 100
155.52    Mbps    Asynchronous Transfer Mode (ATM)
155.52    Mbps    OC-3/STM-1
160    Mbps    Fast Wide SCSI
160    Mbps    Ultra SCSI
274.176    Mbps    DS-4/T4
 320      Mbps      Wide Ultra SCSI
320    Mbps    MicroChannel Card
400    Mbps    FireWire (IEEE 1394)
466.56    Mbps    OC-9/STM-3
480    Mbps    USB 2.0
622.08    Mbps    OC-12/STM-4
640    Mbps    Wide Ultra2 SCSI
1000    Mbps    Gigabit Ethernet
1    Gbps    VL Bus
1    Gbps    PCI bus at 33 MHz bus speed
 1.244      Gbps      OC-24/STM-8
1.28    Gbps    Ultra160 SCSI
1.28    Gbps    Ultra3 SCSI
1.866    Gbps    OC-36/STM-12
2    Gbps    PCI bus at 66 MHz bus speed
2.1    Gbps    AGP 1X port
2.488    Gbps    OC-48/STM-16
2.56    Gbps    Ultra320 SCSI
3.2    Gbps    PCI bus at 100 MHz bus speed
4.2    Gbps    PCI bus 64 bit at 66MHz
4.2    Gbps    AGP 2X port
4.976    Gbps    OC-96/STM-32
8.5    Gbps    AGP 4X port
9.953    Gbps    OC-192/STM-64
10    Gbps    10G Ethernet (IEEE 802.3ae)
13.271    Gbps    OC-255

Nice job buzzjob.com. Some of this will have to be updated, this list doesn't include the latest DDR type system buses, or the 133 megabit per second IDE hard drives, but it gives you the idea.

From Debian we get this slightly dated [2002]but informative piece:

:: Quote ::

The most common PCI bus is 32 bits wide, and operates at 33MHz. Its
maximum throughput is thus 32*33/8 million bytes/second. That's about
132MBytes/sec. Some PCI buses are 64 bits wide at 33MHz, such as on
several popular Tyan Thunder models. Those have a maximum throughput of
264MBytes/sec. Other boards are 64 bits wide at 66MHz, which is limited
to 528MBytes/sec.

In case you've forgotten, one byte = 8 bits.

For more modern boards, this would translate to around:
133 megahertz bus, 32 bit: 4 gigabits per second.
200 megahertz bus, 32 bit: 6.4 gigabits per second.

And now with the latest motherboards claiming a 64 bit 1600 megahertz front side bus, that's so ridiculously fast, what on earth will anyone do with that much speed?
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