Nah - only years of examples of cost cutting in industry.
You wouldn't even be able to tell.
Why? Industry standard practice.
Eh? And you're trying to tell ME that it can't be done? Clue: Design feature 1 - solder runs through the holes connecting the layers.
-- Conor If Pac-Man affected us as kids, we\'d all be running around in darkened rooms, munching magic pills and listening to repetitive electronic music.
Fuck sake. You are incredibly dense. THe same cost cutting techniques used then are also used now. you it would seem.
I don't need to. Its out ther in the interweb. Others have already done it.
I'm going to end this bullshit right here.
Sorry but unless you're a qualified electronics engineer with experience of working to component level - which your stupid statements clearly show you aren't - then your comments are worth precisely f*ck all.
Good day.
-- Conor If Pac-Man affected us as kids, we\'d all be running around in darkened rooms, munching magic pills and listening to repetitive electronic music.
Conor, , the subcutaneous, pedantic bum-bailey, and flusherman in charge of cleaning out the water mains, entreated:
-- Doug Grant wrote: > If you want to respond to my posts... then email me and > I will either allow you to do so or not.
I'm still waiting for even one example of this theory, being implemented.
you're continuing to argue for a method of implementation that requires more to implement. For the control of the solder they'd have to make change... the whole point was to NOT have to change the board at all, only the population of the surfaces.
You really, really DO need to. You claim some vague theory of something that is possible. Yes, if you ignore all the details the designers faced then it may seem possible, but so are other alternatives. Merely citing one thing that is possible is in no way a proof that this is the particular method used.
Along with ego it takes a little REAL HANDS ON to know about specific components. Some generalized theory just isn't worth diddly if you have zero applicable examples. 1987 Pinball machines? LOL. Save your pennies and buy a few motherboard to play with... and I mean play. Poke and prode, test and torture. Get some hands-on then tell us about the port power circuits.
.... snip ...
I surely hope not. That would be a manufacturing nightmare. That's what plated thru holes are for.
-- "If you want to post a followup via groups.google.com, don\'t use the broken "Reply" link at the bottom of the article. Click on "show options" at the top of the article, then click on the "Reply" at the bottom of the article headers." - Keith Thompson
He seems to be thinking of 1987 arcade game boards with features big enough to drive a tank through, and if he insists that (that) is how those old boards were made, I'll take his word for it... but it's a sad state when someone who hasn't even bothered to look at a modern motherboard wanst to argue about how they know what's done on it.
Changes to the power and ground layers are much simpler than changes to the signal layers. No need to change the masks for the signal layers when you can just not populate some components.
It's hard to believe that building two different versions of a board is more economical than just putting in a jumper or a fuse. But often the board without the fuses has other differences. It will be made out of a cheaper material as well. So it's no big deal to make a minor change to the masks for the power or ground layer, in fact the change can be made manually. But there is no reason to change the signal layer masks to remove the pads for the fuse, or the silkscreen.
In many situations it may be true, but much, much simpler is to not change any of the layers.
True, not populate components instead of changing layers.
It cannot be concluded that "it will be made out of a cheaper material" based on this alone. It is possible that some are made of cheaper material, but likewise possible that they are not made of cheaper material. Whether there is a fuse or not is no evidence of it at all.
This is a generalized concept, not any evidence that any (PC motherboards) are currently produced this way.
In fact, the vast majority are definitely not produced this way. If the fuse is omitted they're jumpered, or the surface pads are cotinuous by having a connecting track between them. This is a standard practice and can be observed on any motherboard without a fuse. This is quite specifically why the whole thread exists, because if this method is not being used on this specific board, it is an exception to the rule.
Isn't this thread dead yet???
Whenever possible, MB makers produce one board and then only add components to support the features of a specific model.
It's cheaper to make 10,000 of one board than 2,000 of five different boards.
It also means that the manufacturer can produce more with a specific feature if it tends to sell better and leave off features that don't add value for the customers.
Heh, I'm arguing based more on principle now than any other reason. We have posters making a guess, then trying to conclude that (what is possible) is evidence... without any examples, and without consideration of any other possibilities.
I agree. They're absolutely not going to rework layers even a tiny bit when a simple surface mount component will do.
Hi...
Hey, your arrogance has reached a level of hilarity. Maybe a new reality show should be considered. "Who's in charge of safety certification for every country in the world"
Then again, we know that you are; perhaps you just need to have your staff send out an official letter to the heads of UL, CSA, and all the worldwide rest informing them that you are in charge of how things are to be done?
Ken
The low end boards reduce costs in every possible way. They may be using non-UL approved PC board material, and are probably omitting every non-essential component. They are probably stuffing the minimum number of bypass capacitors, using the "remove capacitors one at a time until the board fails, then add one back" method. This would be the type of board where they would change the power layer to supply +5V power directly to the ports, eliminating the expense of a fuse or jumper, or of adding a trace. There are probably traces going under the fuse, which would make it impossible to add a connecting trace without a board relayout, which is very costly.
I worked for the 2nd largest motherboard company (at the time) and we'd do anything reasonable to save a couple of cents per board, including changes to PCB layers, if the volume was high enough.
Is that a trolling attempt or are you simply ignorant of the fact that there is zero need to change layers for any safety certification?
I never claimed anything remotely near a disregard for any local certification, as any market the product is targeted towards will have such accomodations engineered into it, NOT re-engineering internal layers every time.
Yes, but that is certainly NOT always done by re-engineering or parts substitutions when they also had a more elaborate or more stringent certification necessary for other global regions. This is quite evident with many boards.
No, not every... you're guessing. Even junky, lowest of the major low-end PCChips boards have a few SMD caps, resistors and such going to ports whose physical sockets weren't installed.
Yes they do reduce capacitor counts or quality in "some" designs. This is not new, but cannot be assumed to apply in many cases, either... the boards themselves are the proof, we need not overgeneralize when there are so many concrete proofs of these things.
No, absolutely not. If the upper pads on the top layer are those for the port/features supplied (working) on a particular board, they do MOST DEFINITELY NOT just go and rework the inner layer. How hard is this to grasp? Look at some boards. I don't mean to be rude about this, but you're overgeneralizing to the point where the resulting logic is in error and it's useful to see why that's the case.
It is obvious that with the traces already in place, if there were to be any cost-reduction in layer rework, the very most they would do is bridge the two solder pads, for several reasons. A couple - Power traces (rather than large planes) should not be in inner layers when fine signal lines are above them (as the port data lines are). They heat up more and could delaminate, plus cheap boards tend to have only 4 layers, no ground layer between these so you would have the potential for noise pickup.
You are again jumping to conclusions. We cannot assume "probably", and with all the hundreds (if not more) resistors and caps surface mounted, it is rather trivial to put a 0 ohm resistor across the pads. To even think about doing it any other way costs more than just doing it the same way as (ironically enough) everybody has been doing it.
Still you are drifting along with ideas based around erroneous conclusions. What they do, put simply:
The entire board is designed, period. They do not rework the layers. Surface mounted pads are used, populated for differing compliance and features. This is the way it IS done. Look at some boards. No, look at ALL boards. This is the way it is done. "IF" the board the OP observed, the board that started this whole thread, deviates from this, it is unique in this regard.
However, we still have no evidence that these missing components/pads are actually supply for the implemented ports on that board, rather than there being another trace(s), on the surface layer, for power.
Sure, if there was justification, a way to do so it could be done for some things. That's not evidence that this is what's happening to modern motherboards for port power traces. The motherboards themselves are evidence.
sometimes they use "zero ohm" surface mount resistors, or possibly even surface mount fuse-resistors?
Bye. Jasen
This mobo is an Asrock (Asus) K7VTA Pro rev. 1.02. I don't know if its chipset supports firewire, but there don't seem to be any unused pads that could be used for an optional firewire connector. Also I was wrong about the number of fuses: There's a place for a fourth fuse, in front of the first PCI slot, near the SATA connectors. One pad measures 5V, the other is probably floating because while there's 0V across the pads there's also 0V between that pad and ground. Near each missing fuse are some missing small components, most labelled as resistors or capacitors, others unlabelled.
This is my first experience with Asrock, so I don't know if the mobo is high quality or not, but unlike some ECS and PC Chips mobos where all the electrolytic capacitors are a Taiwanese brand, like OST, some of the caps around the CPU voltage regulator seem to be Japanese because they're brown and labelled "KZT", which I've read is United Chemi Con.
On Wed, 24 Aug 2005 14:48:46 GMT, SMS put finger to keyboard and composed:
I'm in no position to dispute this, but I'm finding it very hard to accept. Have you actually witnessed this?
Have you any idea why the third [open] fuse is there?
- Franc Zabkar
-- Please remove one \'s\' from my address when replying by email.
On 18 Aug 2005 12:03:17 -0700, "larry moe 'n curly" put finger to keyboard and composed:
The only missing feature I can think of that requires +5V power is a firewire port. If there is no real estate set aside for a firewire chip on the motherboard, perhaps it is intended as a future addition to the Via chipset ??? Is there an unpopulated location for a firewire connector?
- Franc Zabkar
-- Please remove one \'s\' from my address when replying by email.
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