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I localized a slow network to a RJ11 network cable.
A new cable made several orders of magnitude difference in terms of speed.
However there was no actual failure in the cable. It worked. It was just slow.
What is the mechanism(s) that allows that to occur?
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Noise being taken in by the cable.
A kink in the cable will can crease a wire, increasing its resistance.
A bad connection to the pins in the RJ45 connector.
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when the cable got damaged, its characteristic impedance may have changed, causing transmission failures at the nominal speed, which the drivers will try and cope with by retransmitting the failing packets until they either arrive well, or a time-out occurs.
Cut the cable in halves, and bin it. Assuming all is well with a new cable, the old one isn't worth anything anymore.
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If it was really RJ11 and not RJ45, then I would guess your old cable was cat3.
CAT3 cable only rates to 10Mbps, cat4 16Mbps, and cat 5 or 6 up to gigabit speeds.
Cat3 cable is can only handle frequencies up the 16MHz while cat5 can handle 100MHz.
You would have to ask an electrical engineer for anything more than that.
Not only do the cables have those ratings, but the jacks and modular plugs do as well.
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Hi,
I understand that Win Vista 64 can use all of 4 gigs, and that Win Vista 32 cannot.
I'm waiting for a friend at MS to send me W7 Ultimate, but in the meantime upgraded my current Win32 system to 4 gigs from 2.
Can't say I notice any real difference in use/programming, even with apps like PhotoShop CS5 where you can allocate more memory usage.
Perhaps if I were using big Excel spreadsheets, or humongous highly-styled documents in Word, I might notice a difference ?
So: the question is: if I give this 2 gigs of ram to a friend who is running Win Vista 64, so he is upgraded to 4 gigs: is that going to do anything real for him ... if he's doing the same kinds of things I am.
And, curious, if, after switching over to W7, the 4 gigs vs. 2 gigs will make any real difference on the OS level.
thanks, Bill
"Many : not conversant with mathematical studies, imagine that because it [the Analytical Engine] is to give results in numerical notation, its processes must consequently be arithmetical, numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine numerical quantities as if they were letters or any other general symbols; and it fact it might bring out its results in algebraical notation, were provisions made accordingly." Ada, Countess Lovelace, 1844
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BillWoodruff wrote: I understand that Win Vista 64 can use all of 4 gigs, and that Win Vista 32 cannot.
There's often a bit of confusion on this subject.
32 bit OS can address maximum 4 gig of memory, 2 gig of program memory and 2 gig of system memory (which includes the memory on the graphic card and all other hardware with addressable memory).
The ratio between program and system memory can be tweaked[^] though.
BillWoodruff wrote:
So: the question is: if I give this 2 gigs of ram to a friend who is running Win Vista 64, so he is upgraded to 4 gigs: is that going to do anything real for him ... if he's doing the same kinds of things I am.
Depends on if the programs he's running needs more than 2 gigs or not. If he never uses that much, he won't notice the two extra gigs.
If he does use more than two gigs he'll notice a big difference as there will be a lot less swapping to the pagefile .
"When did ignorance become a point of view" - Dilbert
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Hi Jörgen,
Thanks for your reply. There is, indeed, a lot of confusion on this, and one reason I posted a question here is that my searching the usual techno-discussion sites for hardware, and MSDN, did not give me a satisfactory answer. Consider the following recent MS page : [^] To me that is a useless resource.
The link you sent me leads to a page which has a warning appear that it does not apply to the operating system I am using (Vista), a link on it to a technet page that promises to reveal BCD settings in Vista, but that contains no specific information on what's specific to Vista vs. older systems.
The implications of what I have read seem to me that the old trick of using the /3G option in the boot.ini file is no longer available in Vista.
However, an alternative technique appears to exist: but consider this comment by an MS Employee on the alternative : [^] If reducing the amount of memory allocated to kernel processes is a side-effect of this technique, then how does one evaluate the potential negative effects of reducing kernel memory ?
A friend of mine who programs full-time in Visual Studio 2010 registered his strong opinion that VS2010 will benefit from 4gb in Win Vista 32, but he's using Win Vista 64
As a test: right now I have one instance of IE9beta, and PhotoShopCS5 open (CS5 has an 80 megabyte file open). The task manager:
1. the green "bar graph" is showing 920 to 1.49 megs of memory being used (it varies).
2. but the read out is showing:
Physical memory
Total 3581
Cached 2340
Free 3
Kernel Memory
Total 133
Paged 95
Nonpaged 38
And 13020 handles open.
Under CS5 Preferences it is showing 1643 megs of memory available.
Thanks for your time, best, Bill Woodruff
"Many : not conversant with mathematical studies, imagine that because it [the Analytical Engine] is to give results in numerical notation, its processes must consequently be arithmetical, numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine numerical quantities as if they were letters or any other general symbols; and it fact it might bring out its results in algebraical notation, were provisions made accordingly." Ada, Countess Lovelace, 1844
modified on Sunday, November 14, 2010 3:13 AM
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The memory limits still applies to all 32 bit OS based on the windows NT Kernel, it's just that you cant use the /3GB switch anymore on Vista and Windows 7 as boot.ini isn't used anymore.
From Vista and forward all boot configuration is stored in "Boot Configuration Data" files that are very well hidden from the users.
To edit them you can use BCDEdit[^] which runs from the command line.
BillWoodruff wrote: If reducing the amount of memory allocated to kernel processes is a side-effect of this technique, then how does one evaluate the potential negative effects of reducing kernel memory ?
The bluescreen will tell you what the problem was.
Think of the scenario where you have the /3GB switch and a graphic card with 1 GB of memory. Then you have no memory for the rest of the system at all.
I would be very careful when I experiment with this.
"When did ignorance become a point of view" - Dilbert
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Hi Jörgen,
Once again, thanks for taking your time to respond !
JA: "Think of the scenario where you have the /3GB switch and a graphic card with 1 GB of memory. Then you have no memory for the rest of the system at all."
While the /3GB is, as you say clearly, no longer relevant to Vista, this is, indeed, a very interesting question: if I interpret this correctly you are referring to a graphic card that consumes 1 gig of ram : so you are implying if you edit Vista with BCDEdit or whatever and have such a card, and have 3/4 gigs allocated for app use, that's a potential fail condition.
Since, in my case I use a graphic card that has 1 gig of DDR3 memory on it (the mainboard uses DDR2), I am not sure that applies in my real-world situation. Unknown to me is whether the memory on the graphic card is irrelevant here in terms of memory usage of the card (I suspect it is relevant). The only thing I asssume, right now, about the memory on the card, which supports DX11 (wasted on me because I'm not a gamer, or 3d wonk), is that it is used by the GPU on the card to handle what is off-loaded to it for computation by specific apps.
JA: "I would be very careful when I experiment with this."
Yes, I am being very careful, and so far it's all academic: until I understand the implications of this throroughly, I'm not about to muck around with these settings, and I intend to upgrade to Win 7 64 bits (now that the drivers are "ripe) asap which, perhaps, changes the whole picture.
Encountering the "blue screen of death" as a possible result of hacking hardware is not on my menu
thanks, Bill
"Many : not conversant with mathematical studies, imagine that because it [the Analytical Engine] is to give results in numerical notation, its processes must consequently be arithmetical, numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine numerical quantities as if they were letters or any other general symbols; and it fact it might bring out its results in algebraical notation, were provisions made accordingly." Ada, Countess Lovelace, 1844
modified on Monday, November 15, 2010 12:15 AM
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BillWoodruff wrote: Since, in my case I use a graphic card that has 1 gig of DDR3 memory on it (the mainboard uses DDR2), I am not sure that applies in my real-world situation. Unknown to me is whether the memory on the graphic card is irrelevant here in terms of memory usage of the card (I suspect it is relevant). The only thing I asssume, right now, about the memory on the card, which supports DX11 (wasted on me because I'm not a gamer, or 3d wonk), is that it is used by the GPU on the card to handle what is off-loaded to it for computation by specific apps.
Your GPU (and all your other devices) use memory mapped IO, which means that the 1GB of memory on your GPU is mapped to 1 GB of your CPUs address space. All other misc devices on your mobo do the same (but typically in much smaller chunks).
3x12=36
2x12=24
1x12=12
0x12=18
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Thanks, Dan,
Illumination is always welcome here in the dark ...
A pretty obvious conclusion if I had really thought about it
best, Bill
"Many : not conversant with mathematical studies, imagine that because it [the Analytical Engine] is to give results in numerical notation, its processes must consequently be arithmetical, numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine numerical quantities as if they were letters or any other general symbols; and it fact it might bring out its results in algebraical notation, were provisions made accordingly." Ada, Countess Lovelace, 1844
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You can always plead Monday and have the charges dismissed.
3x12=36
2x12=24
1x12=12
0x12=18
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BillWoodruff wrote: A friend of mine who programs full-time in Visual Studio 2010 registered his strong opinion that VS2010 will benefit from 4gb in Win Vista 32, but he's using Win Vista 64
Does he know that Visual Studio isn't "/LARGEADDRESSAWARE", and therefore doesn't use more than 2 Gigs? (Ok, that's not true, thats also editable)
BillWoodruff wrote: 1. the green "bar graph" is showing 920 to 1.49 megs of memory being used (it varies).
The keyword here is "being used" as opposed to allocated. If you always have more physical memory than the green bar, then the amount of memory isn't a bottleneck.
"When did ignorance become a point of view" - Dilbert
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Hi Jörgen,
Appreciate all your valuable comments very much !
My friend is using VS 2010 on Win Vista 64 with 8 gigs of memory, so he is probably not even thinking of "LargeAddressWare," but, given his knowledge of hardware and software, I bet he's aware of it.
His specific comment was that VS 2010 would "cache" more given 4 gigs on a 32 bit Win Vista system.
I will read up on "LargeAddressWare," thanks.
best, Bill
"Many : not conversant with mathematical studies, imagine that because it [the Analytical Engine] is to give results in numerical notation, its processes must consequently be arithmetical, numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine numerical quantities as if they were letters or any other general symbols; and it fact it might bring out its results in algebraical notation, were provisions made accordingly." Ada, Countess Lovelace, 1844
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Keep in mind that just because the OS intalled supports a certain amount of RAM doesn't mean the BIOS of the motherboard can use it.
You would probably notice it a lot more with games. Things like loading textures into main memory from disk and then sending them to the graphic card can be helped tremendously by more RAM.
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Hi T M Gray,
Thanks for your response !
The motherboard in question here is a P35 chipset, LGA775 socket, Gigabyte, about three years old, both motherboard and Award Bios, supporting up to 8 gigs in 4 simm slots with optional 800/1066/1333 FSB: in other words, compared to today's premium motherboards, an "antique"
However, you have given me an idea: I wonder if turning on the optional Vista "Aero" effects ... given the increase to 4 gigs of ram ... would now result in no difference in perceived speed of performance.
With only 2 gigs, and Aero glossy-glassy stuff turned on, there was a definite performance hit, which is why I have left them off.
As I said, I don't play any games on this machine other than C# in Visual Studio, so this may be irrelevant.
thanks, Bill
"Many : not conversant with mathematical studies, imagine that because it [the Analytical Engine] is to give results in numerical notation, its processes must consequently be arithmetical, numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine numerical quantities as if they were letters or any other general symbols; and it fact it might bring out its results in algebraical notation, were provisions made accordingly." Ada, Countess Lovelace, 1844
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I am usually pretty good at fixing hardware issues, but this has me baffled...I have a dell 3100 workstation (about 4 years old) which refused to boot after a power outage...pressing the power button does absolutely nothing...no lights in front, no POST. Also, the fan did not spin up at all. Thinking it was probably the power supply, I swapped out the PSU with an older working PSU. The system powered up...problem solved right? I thought so too. A replacement PSU arrived within a week, which I hooked up, but no dice...same as the original PSU...nothing at all happens when the power button is pressed, and the fan (in the PSU) does not spin up with power applied. Weird huh? I tested the PSU with a voltmeter and it is good. The first thing I noticed was that the fan spun up when I shorted the green to black. So why not just keep the PSU that is working in it and forget about it?...because I can't put the case cover on with the working PSU, (the SATA power connector for the HD is not right-angle like the proprietary Dell PSU...also, the original PSU uses a 24 pin MB connector, and the working one uses a 20 pin. (actually, that I could live with) As I said, the PSU that works is a 20 pin MB connector and neither of the PSUs with 24 pins work at all, even though they test as good. Any ideas?
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I don't have that type of computer, but I would check to see what is common between the 2 power supplies that don't work and different with the one that does. Is there a power cable different? Is there some sort of safety switch?
I'd venture a guess that there is a poor connection somewhere. A voltmeter can read fine, but once you draw some current, the voltage drops.
Good luck and let us know what you find out!
CQ de W5ALT
Walt Fair, Jr., P. E.
Comport Computing
Specializing in Technical Engineering Software
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Thanks for the response! I have another box with a 24 pin MB connector that works. (although with the 20 pin MB connector attached) I think I'll take the time to try the PSU that I bought in that one. If it doesn't work, then I have to assume the PSU is bad, and will just get them to send me another. Will post back tonight with the results.
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Yep, that would do it...now if I can just find these local, or spend $5 shipping for a $4 part! Thanks for the post!
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I linked to amazon because it's eligible for free shipping if you tack it onto an existing order. IIRC Google turned up one for $6 or 7 shipped.
3x12=36
2x12=24
1x12=12
0x12=18
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OK, this has me beat...
I have a 1GB CompactFlash card I want to use in my camera, and it shows up fine in Windows explorer with a single 61 MB partition and 923 MB of free unallocated space.
1) I right click on the allocated space and the option delete the volume is greyed out. I can format it, but I can't repartition the card at all.
2) All I can do on the unallocated space that shows up is a few options about adding spanned, stripped, and mirrored volumes.
3) The card itself has no switch on it to place it into 'read only mode' or 'protected mode' and I assumed that would have also blocked the formatting so...
I have formatted CF cards on my machine before without issues... but this Lexar card is kicking my butt for some reason. Keep in mind that it DID start out with this 61 MB partition as a bootable one (originally used as a HD for a small scale embedded VM system) and was running a a copy of ROM DOS.
Any one out there with any ideas?
Hate to just toss a 1 GB CF card in the trash if I can save it and use it with my camera.
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Two ideas:
1.
Have you tried the Computer Management utility? It is part of Windows (since XP IIRC), and allows you to resize existing partitions and create new ones, at least on regular disks. I don't know what it will offer for CompactFlash though.
2.
Some USB sticks come with extra software that basically offers two partitions, a small unprotected one, and a second, encrypted one, that becomes visible and read/writable only once that software has been launched with the right password.
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Luc Pattyn wrote: Have you tried the Computer Management utility?
Yeah, that's where I do everything. Hmmm what I have NOT tried though is just plan old FDISK... might be worth it. Maybe something like Norton...
Luc Pattyn wrote: Some USB sticks come with extra software
Nah, not on these guys.. I know what's on them... I just have an odd feeling that windows is somehow freaking because the primary partition on this card WAS bootable, but looking it at shows no signs of any hidden files left, or anything odd like that. Might just end up digging around at the fdisk layer a bit...
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