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I'm wondering if it is possible to generate pure randomness with a typical PC.
I'm thinking there might be hardware within the PC that runs at different clock frequencies with electronic variances that can be used to generate a stream of pure randomness.
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I think "generate pure randomness" is an oxymoron. The best you can do is use a source that is highly variable and not predictable. APIs like CryptGenRandom() sample dozens of system parameters to come up with a source that changes so much as to make it unpredictable. Or you could rig up something similar to LavaRand. 
--Mike--
Visual C++ MVP 
LINKS~! Ericahist | 1ClickPicGrabber | NEW~! CP SearchBar v3.0 | C++ Forum FAQ
Laugh it up, fuzzball.
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No, you'd need external hardware to do this. The built in sensors are only sensitive enough to detect problems, not record pure noise like you'd need for a RNG.
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One way, that I've seen other site's recomend, is to play some noise in the speakers, then record the sound with a microfone. Then you'll get something very close to random.
The one and only Niklas Ulvinge aka IDK
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If you want to generate randomness interms of numbers,
then you can add some huge numbers and make overflow in the register.
The generated number everytime will be the random number
Anil Kumar
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When I start my computer, it doesn't connect to the screen...
The screen only goes into powersaving mode, wich it does when it doesn't connect to the PC...
The one and only Niklas Ulvinge aka IDK
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Do you have a 2nd monitor/pc available? If so switching screens will show if hte problem is hte monitor or the PC.
If not, do your PC give the normal beep(the on boot beep is an errorcode) when you turn it on? If it does the problem's your monitor, if not your PC. If it's your PC, we need to know it's model and how it's beeping differently to diagnose the problem.
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Yes your right, it's bios error, it won't beep at all when I start it
I've been mixing a little with some harddrives and cd drives... But that can't be the problem, couse bios would start anyway...
I hear everything spin up, but then I don't know what happends...
The one and only Niklas Ulvinge aka IDK
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If it's not beeping the problem is probably something other than the bios. A failing power supply (bringing some power but not enough), or dead cpu would be more likely. If you have a multimeter you can check the former. Stick the probes into both a spare drive connector and the one on the mobo (a loose connection, or failing mobo parts could make the voltage levels different here than on a drive connector). Black to Red should be 5V, Black to Yellow 12V. A deviation of +-5% is within accepted bounds, more than that could be the problem.
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OK, I don't got a multimeter... I think my dad got one, but he's  now.
I'll have to do it tomorrow...
The one and only Niklas Ulvinge aka IDK
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Niklas Ulvinge wrote: The screen only goes into powersaving mode, wich it does when it doesn't connect to the PC...
I take it this same screen and graphics card have worked together before?
You'll have to forgive me for asking a few questions before I can say anything else.
Does the machine actually turn on and post? You should hear one short beep on startup. If you hear any other number of beeps look here[^] if you hear "no beeps" indicating no POST operation occurs take it to a shop, or look here.[^]
outside of that, you can check to make sure the VGA cable is connected tight (a loose connection can decide to move enough to stop connection just by time and gravity). Make sure you have the right VGA cable connected (some monitors have more than one input).
Without more information on what is happening durint POST I can't help much. If it is the video, and you have a friend who lets you open up machines, you can swap video cards. If your computer boots normally on his card, and his computer does not show video, you know the problem is with the graphics card and can replace it (thank him with a beer/soda as per his preference and head off to the store).
The easiest way to troubleshoot failed technology is with spare parts, making it more difficult for the average person. With some more details on what the computer is doing, can you pop the case open (preferably without damage) and peek to make sure the video card is plugged in, CPU fan starts turning (and GPU fan if appropriate). Any northbridge cooling that is on the motherboard also, basically if it has a fan, make sure it is turning. If not, that's a strong indication of where a problem started, though it may not end there.
_________________________
Asu no koto o ieba, tenjo de nezumi ga warau.
Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
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Thanks for your reply.
Read my other post...
I didn't think of the possibility of bios errors...
The one and only Niklas Ulvinge aka IDK
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Does anyone have a link or article featuring the components and roles of the video card? If you also have a link or article for data routing in video capturing (recording and previewing) it would be much appreciated... This is because I want to know how it is related to video recording. We are having problems with simultaneoudly capturing video using 4 usb webcams(same brand and model). We pin-pointed that the video card may be the source of our problem... Thank you very much... 
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I can't find the one I was looking for. This may help a little as far as explaining the complexity of the graphics system: Windowing_System_on_a_3D_Pipeline_Slides.pdf[^]
Now, until Vista, the windowing manager is not within the 3D pipeline, it is consider a raster only process. Most of a raster process in the IO to the card.
_________________________
Asu no koto o ieba, tenjo de nezumi ga warau.
Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
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Thank You Very Much! 
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I'm looking for a cheap laptop (probably new not second-hand) for a student. Mainly for word processing, a bit of spreadsheet stuff, etc. Certainly no programming, and I don't care about games!
Since it is certain to be lost / stolen / broken / filled with coffee, I have no interest in buying anything even remotely state-of-the-art.
I have seen a laptop using 1GHz VIA C1, 256Meg RAM, 40Gig HD, WinXP Home, for 25% cheaper than any other new laptops. Any comments?
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IIRC the via chip only does half/cycle as a p3/athlon does, so performance wise it's a athlon 500, or p4 650. Shouldn't matter for what you intend but you should be aware of what you're actaully getting.
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Thanks.
For what it's worth, I got the processor wrong - it's a VIA C3, not C1.
I found some reviews (Tom's Hardware, etc) which indicate that the floating point unit on a C3 is lousy.
On benchmarks, the 1GHz C3 performs between a 433MHz Celeron and a 1GHz Celeron (depends on the test.)
Since I was happy until recently with my 667 MHz Celeron (when I wasn't building projects in Visual Studio 6), a student can live with a 1GHz C3 notebook!
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I've got a compaq presario notebook with a relatively small and slow 60Gb/4,200rpm drive. I want to upgrade to something bigger and faster but I'm having trouble finding info on the type of drive I need.
The drive I have has 2 rows of female connectors. The drives I've seen have 2 rows of male connectors. I'm assuming this is a UDMA/ATA issue but googling has only muddied the water.
Can anyone give me the low-down?
cheers,
Chris Maunder
CodeProject.com : C++ MVP
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Whats the model of your notebook? I have only seen notebook HDDs with male connectors.
Farhan Noor Qureshi
if (this == this) thow this;
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Compaq Presario 2140CA
cheers,
Chris Maunder
CodeProject.com : C++ MVP
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Well found this pdf[^] on this page[^]. On page 5-16 of this pdf look for "To Replace the Hard Drive Holder". This section mentions how to reuse "holder" from old HDD. I hope that helps.
Farhan Noor Qureshi
if (this == this) thow this;
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[Edit: Mystery solved. Your pointer to the PDF about the holder made me open up the case again to have another look. Lo and behold there's a gender-bender attached snug to the HDD. I'm back on track]
Thanks! Just a pity that the illustration and what I have in front of me are completely different!
No holder, just a HDD with female bits.
cheers,
Chris Maunder
CodeProject.com : C++ MVP
-- modified at 16:40 Thursday 27th October, 2005
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Glad to hear this.
Farhan Noor Qureshi
if (this == this) thow this;
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Hello,
I am developing a project and l need to be able to access the infrared port on my computer.
My project has 2 applications that run on 2 notebook computers. I have data that I have on one notebook that has to be sent to another notebook.
The client will click a button and all the data that is being displayed in the text boxes will be sent to another notebook to be displayed in some other text boxes.
Does anyone know how to do this. I am using the c# language.
Thanks in advance,
Steve
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