Contour Enthusiasts Group Archives Forums General Common Interests Computer gurus: Round parallel ATA vs. Ribbon?

I understand that when ATA 66 was released a new ribbon cable was introduced that has ground wires running in-between each wire in the ribbon to reduce the effects of cross-chatter. Now round parallel ATA cables are available, but I have heard that in ATA 66/133 setups they reduce performance because of cross-chatter between the wires. Is that true? Am I better off running ribbon cable instead? What about the round ata cables that say they support ata 133, do they experience cross chatter?
Thanks,

Rounded cables are mostly to decrease obstructions in air flow and to give the cases interior a cleaner look. As far as the cross talk I can't say for sure but here's what I do know. Rounded cables were created from ribbon cables(by cutting in between the wires) by pc enthusiasts who are all about squeezing every ounce of performance out of their machine. I don't think their would be OK with a performance decrease, and if there is one it's negligible. Whenever you have wires in close proximity to each other there's going to be some cross talk.

From what I have heard. It is better to run flat ribbon cables because of the crosstalk problems with the rounded cables. But it is not all that much of a problem and most people will be fine with the rounded cables.

Have you considered running Serial ATA instead if you want small cables ?

You would need to get converters for all your regular hard drives.

Why not SCSI or Fibre Channel drives if you want the ultimate in performance?

TB

How much can it really matter, an ATA-133 drive (or even a SCSI or FC drive) only has so much cache until you are limited by the physical access speed of the drive. So after you exhaust 8M or so of on drive cache, you then have to wait for disk access.

I used this example when I would teach, so the numbers are a bit old, but today the peformance difference is even greater.

Take a disk drive with 10ms access time and compare it with RAM that has a 60ns access time. (I know today's RAM is even faster, but work with me here.)

Let's convert these into numbers we all understand. Since you and I don't deal well with 60nS, let's just change that to 60 seconds. So we take 60ns and multiply by 10^9 to get 60.

But we have to do the same with the 10ms drive access time. When we multiply 10ms by 10^9 we get 10^7 seconds access time.

Do you realize how long 10^7 or 10 million seconds is? There are 86400 seconds in a day, so we are looking at something like 115 days.

That is the difference between drive access speeds and RAM. What you can fetch from memory in 60 seconds can take the equivalent of 115 days to get off a disk, if we transpose the times to things humans can understand.

So those ATA-133 drives may be able to fill the channel for short bursts, most of the time, you simply are waiting for the head to move, and the platter to rotate.

So I wouldn't worry about flat vs ribbon cable for drive performance.

I'd buy more RAM.

TB

I went serial ATA...I'll never go back. The cables are so easy to route around the case and the burst speeds are great.

14000 rpms!! dang thats really good for rendering.