With serial transfers, if you can maintain data integrity at both ends, you can clock up pretty easily. With parallel, you have not only the endpoints, but the transmission to consider in the engineering. The lines have strict tolerances as far as relative length to each other to preserve timing without compensating for it at the endpoints, also parallel lines have to contend with parasitic capacitance,among other things, that occurs between the wires on the bus.
That is not to say that parallel technology cannot be ramped up, it's just that it tends to be a greater engineering challenge and more expensive at the onset. So, high speed serial transfer technology wins for now. What Hat Monster meant when he said "it isn't", is that a hard drive running on a Serial ATA interface isn't going to be any faster than the same hard drive running on a standard ATA interface.
Yes, but wouldn't a faster bus speed mean better system performance, regardless? The local bus spends less time tied up transferring disk data to memory, and any time not used by disk transfers can be used for other things.
Anyhow, the main problem with parallel is Eight or sixteen times as many lines certainly would mean eight or sixteen times the bandwidth - theoretically. With all these wires so close together, though, their electric fields start interfering with each other and generating false signals, and the faster the clock, the worse the crosstalk. Serial cables with fewer lines have MUCH less crosstalk, and can also use fancy stuff like balanced signals to make them go even faster.
Just about every serial protocol but the old standby RS uses balanced signals these days. Is parallel IDE still possible at higher speeds? I think so, but not without rewriting their cable design from scratch; and a revamped parallel design's not likely to be as cost-efficient as serial ATA is now. Next step, universal optical bus! Not really. The PCI bus or even the southbridge that your IDE controller is hooked up to very rarely saturates all available bandwidth for any appreciable amount of time-- particularly if your southbridge has a very fast transport link.
Well, it's not quite THAT simple, or else some of the orgami-folded ribbon cables would have higher error rates, too. Browse All Windows Articles. Windows 10 Annual Updates. OneDrive Windows 7 and 8. Copy and Paste Between Android and Windows. Protect Windows 10 From Internet Explorer. Mozilla Fights Double Standard. Connect to a Hidden Wi-Fi Network. Change the Size of the Touch Keyboard. Reader Favorites Take Screenshot on Windows. Mount an ISO image in Windows.
Boot Into Safe Mode. Where to Download Windows Legally. Find Your Lost Product Keys. Clean Install Windows 10 the Easy Way. The Best Tech Newsletter Anywhere Join , subscribers and get a daily digest of news, geek trivia, and our feature articles.
How-To Geek is where you turn when you want experts to explain technology. Since we launched in , our articles have been read more than 1 billion times. Easy cable management and cable length.
Increased airflow. Support for more drives. Drivers and support. One drive per cable. First of all: It isn't. Then, of course parallelizing several data lines lets you transmit more data. But so does making the individual lines transmit faster. Doing the latter wins you real estate - in chip pin count, mainboard trace routing, connector sizes on both ends, and cable width.
This is what the move to SATA is all about. Not speed. Mar 21, 0 0. So, there is a limit for this. Jan 6, 0 I think Serial is easier to push up in speed since you won't have to deal with syncing multiple signals. However, Parallel does have the advantage of pushing more than one signal. Devistater Diamond Member. Sep 9, 3, 0 0. Also notice that cable length is important. Because for parallel as mentioned above you need to keep in sync, the official IDE cable length limitation is 18" Yes I know a lot of companies sell rounded cables of 24" or so, this is longer than standard and carries some risk In SATA you can have longer cables since you dont have to sync the data in parallel any longer.
Apr 22, 7, 0 0. Originally posted by: Peter First of all: It isn't. Jan 4, 7, 10 Originally posted by: rgwalt Originally posted by: Peter First of all: It isn't. Dec 13, 0 0. Serial is faster because instead of having 32 or 64 parallel data line send bit by bit - you have two serial lines one in - one out but the data is organized into packets similar to networking so you are sending packets or datagram? The same thing goes with the new PCI-X slots that are coming out.
They work the same way, packets, and datagram? Think about it. Now that we have motherboards with dual gigabit networking, 7. That is why the mobo manufacturers are doing away with the pci bus and going with pcix. Right now mobos have both so you do not have to throw away your pci stuff that is still good, but eventually pci will go the way of the isa bus.
Spencer Diamond Member. Oct 11, 3, 0 0. Parallel interface can always be made faster then serial interfaces. The main reason to replace parallel with serial is cost. Sure serial is faster when it comes out but that is only because they break backwards compatiblity.
If you where to create a completely new parallel standard for hard drives you could easly get speeds much higher then SATA but there simple is no reason to.
Sep 16, 0 0. A long time ago, parallel was preferred because the limitations to speed were in the copper wires themselves. You simply couldn't push a very fast signal through, so the need to put multiple signals together was used.
However, as you know, technology changes. The main problem now is skew, crosstalk, noise, etc.
0コメント