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#11
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Some pathetic excuse for a bull**** artist desperately cowering behind
John H wrote in message ... just the puerile attempts at insults any 3 year old could leave for dead. |
#12
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Rodney's down under is ausie land. He only has to worry about the dingos.
"John H." wrote in message ... | To tell you the truth Rod, your posts (when you start with the silly | stuff) make me laugh more than get angry. That must be why you've | gotten away with it for so long. | | There was a case a few years back where some guy in New Jersey mouthed | off to a guy in NYC. Turned out the NYC guy was in a street gang. | The gang looked the Jersey guy up and put him in a hospital - damn | near killed him. So be careful, you never know who you're talking to. | | | I can believe you're an older guy, your language is far too clean for | a pimple-faced teenager. | |
#13
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On Fri, 01 Aug 2003 01:10:14 GMT
John H. wrote: On Thu, 31 Jul 2003 19:09:59 +0000, "J.Clarke" wrote: The case manufacturers have to consider RF emission regulations. Big holes in the case let RF out, so they make a lot of small holes over the fan mounting positions instead. That's sounds like a reasonable explanation. A round-wire finger-guard like what a power supply uses wouldn't work well enough for that? If it's making metal-to-metal contact with the case and the wire spacing is close enough. But that's an additional assembly step that most PC manufacturers don't want to spend the labor to perform--on one machine it's peanuts, on a few thousand it adds up. I wonder how many of us have cases that meet those regulations, with missing slot covers and the like. I had to 'snap out' a slot cover to install my HD in a 5.25" slot and there's no way to cover it up again. I also have the side covers off my case for the time being. I suspect that most hobbyists machine leak like sieves, but unless our machine is generating enough noise to result in a complaint being filed, we don't get investigated. OTOH, a PC manufacturer, even the strip-mall computer shop variety, can get in fairly serious trouble if their machines, as-shipped, don't comply. -- -- --John Reply to jclarke at ae tee tee global dot net (was jclarke at eye bee em dot net) |
#14
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John H wrote in message ... Rod Speed wrote John H wrote It's easy enough to just try it and see. If there's a problem, try something else. You werent suggesting trying it, you proclaimed that its necessary. Necessary for ME, to do what I wanted. Wrong. Again. And you previously claimed that that config was NECESSARY for on the fly CD copying. You are just plain wrong. Judging from this group, both configurations are common. Separate issue entirely to what is NECESSARY for on the fly CD copying. Probably the main reason I have my drives on different channels is because I didn't want them next to each other in 3.5" bays without good cooling. You dont need the massive overkill of 8 3.5" slots to get that. Your "massive overkill" is probably no more than an extra $20 if you compare cases with 4 or 8 3.5" bays from the same manufacturer. 'same manufacturer' is completely irrelevant andyou are just plain wrong on that $20 claim anyway with some of them. What's your problem with that? Thats its stupid to be claiming that that is anything like the 'best mid-tower case for a home system' when almost no one demands that stupid requirement. So a $1500 system goes up to $1520. Big deal. You've just plucked those utterly bogus numbers out of your arse. Most all cases intended for home use are cheap as dirt now compared to what they used to cost. Completely irrelevant to whether 'best mid-tower case for a home system' needs to have that many 3.5" drive bays. I usually spend more for one night out. Your problem. The Lian-Li PC-60 is no taller, about an inch wider and 5 inches deeper (~23") than my present case (~18"). Completely irrelevant to whether its anything like the 'best mid-tower case for a home system' Pity its MUCH more expensive than perfectly adequate mid tower cases. That's not a problem for me so I think it's a good trade-off for the extra good cooling and add-on room. More fool you. Other cases with 6-8 3.5" bays Only a fool demands that for a home system. may be smaller - I haven't looked around much yet. I've had much taller cases (full tower) but not one this deep. Maybe the case is too big for you, Wrong. Again. Just ridiculously over priced. and that's fine, and why there's hundreds of cases to choose from - one size does not fit all. Gone blind yet ? If your case has a better layout or more 3.5" slots, you have more options than I did. Plenty of cases around with more than 3 3.5" bay slots. I know, the Lian-Li has 8. :-) Pathetic, really. I could have bought an add-on cage to hold two more 3.5" drives for the case I have now but I didn't do it because I started with one drive and didn't plan ahead very well. Too late now. The cooling would have sucked anyway. You dont need a case with 8 3.5" drive bays. Wrong again. Wrong again. Very helpful. Pathetic, really. |
#15
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Some pathetic excuse for a bull**** artist desperately cowering behind John H wrote in message ... just the puerile attempts at insults any 3 year old could leave for dead. |
#16
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"Rod Speed" wrote: "Timothy Daniels" wrote: "Rod Speed" wrote: Timothy Daniels wrote: Rod Speed wrote Timothy Daniels wrote: As for cables, have you looked into a set of "round" cables, such as by Vantec (see http://vantecusa.com/ide.html ) which come in lengths which may accommodate your drives' spacing? Those flout the ATA specs. I wouldnt use them myself. Where can one find these ATA specs on the Web, http://www.t13.org/ and how do "round" cables flout them? The main problem is that the 80 wire standard has a ground line between each signal line to provide something close to a reasonable transmission line and to isolate the signal lines from each other. Even if the round cable is just a ribbon cable rolled up, you clearly get signal lines next to each other in a way that you dont with a flat ribbon cable. Even worse when the round cable isnt a ribbon cable rolled up. I called Vantec about pairing of signal polarities (such as is done with Cat 5 cable), That cant be done with a PATA drive because the differential signals that are used in that config arent even present. What can be done is to have a twisted pair with one of the wires a ground wire. I just checked my round cables (not yet installed), which were made by Vantec, and there are 80 conductors where each of the 40 colored conductors is twisted with a white conductor. A call to Vantec confirmed that the 40 white conductors are grounded. I also looked at the SVC website, and it says that its round IDE cables consist of 80 conductors with 40 twisted pairs. I have no idea if other brands have only 40 conductors, but it would appear that the twisting of a signal conductor with a ground conductor would go far to cut down crosstalk - as would opting for shorter cables when one has a choice. *TimDaniels* |
#17
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"Timothy Daniels" wrote in message ... "Rod Speed" wrote: "Timothy Daniels" wrote: "Rod Speed" wrote: Timothy Daniels wrote: Rod Speed wrote Timothy Daniels wrote: As for cables, have you looked into a set of "round" cables, such as by Vantec (see http://vantecusa.com/ide.html ) which come in lengths which may accommodate your drives' spacing? Those flout the ATA specs. I wouldnt use them myself. Where can one find these ATA specs on the Web, http://www.t13.org/ and how do "round" cables flout them? The main problem is that the 80 wire standard has a ground line between each signal line to provide something close to a reasonable transmission line and to isolate the signal lines from each other. Even if the round cable is just a ribbon cable rolled up, you clearly get signal lines next to each other in a way that you dont with a flat ribbon cable. Even worse when the round cable isnt a ribbon cable rolled up. I called Vantec about pairing of signal polarities (such as is done with Cat 5 cable), That cant be done with a PATA drive because the differential signals that are used in that config arent even present. What can be done is to have a twisted pair with one of the wires a ground wire. I just checked my round cables (not yet installed), which were made by Vantec, and there are 80 conductors where each of the 40 colored conductors is twisted with a white conductor. A call to Vantec confirmed that the 40 white conductors are grounded. I also looked at the SVC website, and it says that its round IDE cables consist of 80 conductors with 40 twisted pairs. Trouble is that the standard specifys something completely different, a flat ribbon cable with every second wire grounded. Electrically they aint the same at all. I have no idea if other brands have only 40 conductors, I doubt it with better than ATA33 cables. They are usually either that twisted pair arrangement or a ribbon cable rolled up. Both approaches are electrically very different to what the standard specifys. They are often longer than the standard allows too. In short they flout the standard. but it would appear that the twisting of a signal conductor with a ground conductor would go far to cut down crosstalk Its more complicated than that. Twisted pairs should be driven differentially, just just a ground twisted with the signal line. - as would opting for shorter cables when one has a choice. Makes a hell of a lot more sense to use flat 80 conductor ribbon cables that meets the standard instead. Even if that means that you have to choose a case that allows the use of those. |
#18
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"Rod Speed" wrote: "Timothy Daniels" wrote: "Rod Speed" wrote: "Timothy Daniels" wrote: "Rod Speed" wrote: Timothy Daniels wrote: Rod Speed wrote Timothy Daniels wrote: As for cables, have you looked into a set of "round" cables, such as by Vantec (see http://vantecusa.com/ide.html ) which come in lengths which may accommodate your drives' spacing? Those flout the ATA specs. I wouldnt use them myself. Where can one find these ATA specs on the Web, http://www.t13.org/ and how do "round" cables flout them? The main problem is that the 80 wire standard has a ground line between each signal line to provide something close to a reasonable transmission line and to isolate the signal lines from each other. Even if the round cable is just a ribbon cable rolled up, you clearly get signal lines next to each other in a way that you dont with a flat ribbon cable. Even worse when the round cable isnt a ribbon cable rolled up. I called Vantec about pairing of signal polarities (such as is done with Cat 5 cable), That cant be done with a PATA drive because the differential signals that are used in that config arent even present. What can be done is to have a twisted pair with one of the wires a ground wire. I just checked my round cables (not yet installed), which were made by Vantec, and there are 80 conductors where each of the 40 colored conductors is twisted with a white conductor. A call to Vantec confirmed that the 40 white conductors are grounded. I also looked at the SVC website, and it says that its round IDE cables consist of 80 conductors with 40 twisted pairs. Trouble is that the standard specifys something completely different, a flat ribbon cable with every second wire grounded. Electrically they aint the same at all. I have no idea if other brands have only 40 conductors, I doubt it with better than ATA33 cables. They are usually either that twisted pair arrangement or a ribbon cable rolled up. Both approaches are electrically very different to what the standard specifys. They are often longer than the standard allows too. In short they flout the standard. but it would appear that the twisting of a signal conductor with a ground conductor would go far to cut down crosstalk Its more complicated than that. Twisted pairs should be driven differentially, just just a ground twisted with the signal line. - as would opting for shorter cables when one has a choice. Makes a hell of a lot more sense to use flat 80 conductor ribbon cables that meets the standard instead. Even if that means that you have to choose a case that allows the use of those. I agree with you that round cables flout the specs. I also agree that twisting provides the best noise immunity when the pair of wires are driven differentially. But there is still a degree of immunity provided when one of the wires in a pair is grounded. The signal travelling along the pair is still just the instantaneous value of the voltage between the "signal" wire and the ground wire instead of the voltage between the "plus" and "minus" signal wires. It has only half the noise immunity because the signal is half what it would be if paired with its opposite value, and so environmental noise seems twice as large. In the case of the 80- conductor ribbon cable, the ground wires are on two sides of signal wire, but they are not twisted, which makes them vulnerable to certain noise modes that twisting protects against. The round cable also provides an outer metal braid for shielding, which the ribbon cable does not. The bottom line, I think, is that round cable is harder to specify and so standards for round cable were just never defined. So round cables do flout the specs, but that doesn't necessarily mean that their noise immunity is worse. It just means that "your mileage may vary" somewhere between Better and Worse. *TimDaniels* |
#19
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"John H." wrote: ....I'm considering a Lian-Li case that has vertical HD mounting but I worry about the possibility of gyroscopic effects causing a head crash if the computer is accidently moved while operating. Is horizontal mounting safer? Maybe there's a reason why practically every other case manufacturer uses horizontal mounting even though vertical mounting is more space efficient. Dell makes pretty good PCs and PC cases, and my Dell Dimension mounts its hard drive(s) vertically. The location is right at the bottom front of the case where it gets a steady supply of cool room temp air, and being vertical, the hard drive(s) also get the added benefit of convection currents - really good in case one of the exhaust fans fail. For cooling considerations, I think vertical mounting is superior to horizontal mounting for *anything* (as long as there is ambient air and gravity has an effect). *TimDaniels* |
#20
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"Timothy Daniels" wrote in message ... "Rod Speed" wrote: "Timothy Daniels" wrote: "Rod Speed" wrote: "Timothy Daniels" wrote: "Rod Speed" wrote: Timothy Daniels wrote: Rod Speed wrote Timothy Daniels wrote: As for cables, have you looked into a set of "round" cables, such as by Vantec (see http://vantecusa.com/ide.html ) which come in lengths which may accommodate your drives' spacing? Those flout the ATA specs. I wouldnt use them myself. Where can one find these ATA specs on the Web, http://www.t13.org/ and how do "round" cables flout them? The main problem is that the 80 wire standard has a ground line between each signal line to provide something close to a reasonable transmission line and to isolate the signal lines from each other. Even if the round cable is just a ribbon cable rolled up, you clearly get signal lines next to each other in a way that you dont with a flat ribbon cable. Even worse when the round cable isnt a ribbon cable rolled up. I called Vantec about pairing of signal polarities (such as is done with Cat 5 cable), That cant be done with a PATA drive because the differential signals that are used in that config arent even present. What can be done is to have a twisted pair with one of the wires a ground wire. I just checked my round cables (not yet installed), which were made by Vantec, and there are 80 conductors where each of the 40 colored conductors is twisted with a white conductor. A call to Vantec confirmed that the 40 white conductors are grounded. I also looked at the SVC website, and it says that its round IDE cables consist of 80 conductors with 40 twisted pairs. Trouble is that the standard specifys something completely different, a flat ribbon cable with every second wire grounded. Electrically they aint the same at all. I have no idea if other brands have only 40 conductors, I doubt it with better than ATA33 cables. They are usually either that twisted pair arrangement or a ribbon cable rolled up. Both approaches are electrically very different to what the standard specifys. They are often longer than the standard allows too. In short they flout the standard. but it would appear that the twisting of a signal conductor with a ground conductor would go far to cut down crosstalk Its more complicated than that. Twisted pairs should be driven differentially, just just a ground twisted with the signal line. - as would opting for shorter cables when one has a choice. Makes a hell of a lot more sense to use flat 80 conductor ribbon cables that meets the standard instead. Even if that means that you have to choose a case that allows the use of those. I agree with you that round cables flout the specs. I also agree that twisting provides the best noise immunity when the pair of wires are driven differentially. But there is still a degree of immunity provided when one of the wires in a pair is grounded. Not really, particularly when you have sets of those twisted pairs all crammed together in an outer jacket. The signal travelling along the pair is still just the instantaneous value of the voltage between the "signal" wire and the ground wire Nope, all the grounds are commoned at each connector, the line receiver doesnt see both the ground and the signal line. instead of the voltage between the "plus" and "minus" signal wires. Yep, thats the only way a twisted pair can work. It has only half the noise immunity Thats nothing like the electrical reality. because the signal is half what it would be if paired with its opposite value, It doesnt work like that. and so environmental noise seems twice as large. Nor that either. In the case of the 80-conductor ribbon cable, the ground wires are on two sides of signal wire, Yes, the ground wires provide significant electrical isolation between the adjacent signal lines. And a more stable impedance as well. but they are not twisted, which makes them vulnerable to certain noise modes that twisting protects against. Not when it aint driven differentially it doesnt. AND the drivers and receivers are designed for the electrical characteristics of that particular config. The round cable also provides an outer metal braid for shielding, These are digital lines, not analog. They dont need a shield braid. which the ribbon cable does not. Doesnt need that. The bottom line, I think, is that round cable is harder to specify and so standards for round cable were just never defined. Thats must plain wrong too. Round cables with twisted pairs are in fact defined in some standards like CAT5 and SATA. So round cables do flout the specs, but that doesn't necessarily mean that their noise immunity is worse. It aint about immunity to noise, its about crosstalk and avoiding impedance discontinuitys which produce reflections with unterminated cables. It just means that "your mileage may vary" somewhere between Better and Worse. Wrong. The drivers and receivers are designed to get adequate performance out of the correctly specified 80 conductor flat ribbon cable. Pointless utterly flouting those specs. If you do want a round cable for whatever reason, the only thing that makes any sense is to use SATA instead which just happens to have proper formally specified round cable in that standard. Round PATA cables are only used by those who havent got a clue about the electrical basics. |
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