Wikipedia:Reference desk/Archives/Computing/2014 April 14

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April 14

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Free alexa rank tracking site

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Is there any free site like siterankhistory.com that tracks Alexa ranking? --TitoDutta 05:08, 14 April 2014 (UTC)[reply]

Alexa.com is what you're looking for. Just enter in the website url you want to check in the box. 123chess456 (talk) 00:42, 15 April 2014 (UTC)[reply]
For what particular site? Alexa only gives the history for free if the website is very popular. You'll probably have to pay if you want the information, unless you're willing to try archive.org, but I think the results are dynamically generated and won't be available on archive.org. Anyways, you asked for "Alexa rank tracking". The only company with access to Alexa's information on ranking is Alexa itself, any other site that has information that Alexa charges for and is giving that information out is violating Alexa's Terms of Service 123chess456 (talk) 01:05, 15 April 2014 (UTC)[reply]

Why does APU need UMA framebuffer?

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For an accelerated processing unit that can access all of main memory, what's the advantage to setting a UMA framebuffer in BIOS, versus having the operating system allocate only the amount of memory a specific shader or OpenCL kernel needs? Is it that address translation is bypassed? NeonMerlin 14:01, 14 April 2014 (UTC)[reply]

Are you sure you can set a UMA frame buffer in the BIOS (more likely UEFI) when you have a hUMA/HSA processor? Or to put it a different way, when you set it, does it actually do anything, does e.g. the amount of memory available to the CPU change in your OS system settings? It wouldn't surprise me if the UMA frame buffer setting is simply something which should disappear but doesn't when you install a hUMA processor under the UEFI of whatever motherboard you're referring to and has no actual effect when a hUMA processor is installed. Modern UEFIs are often better than older BIOSes at hidden settings which are irrelevant, but their designers still make mistakes sometimes. Remember the FM2+ mobos support all FM2 APUs so having a non hUMA APU in the mobo should be a design expectation (and anyway AFAIK most of them are just FM2 mobos with minor changes needed to support FM2+), so the setting definitely needs to be there in for some cases. In fact, it wouldn't surprise me of the setting is still there when you install a CPU [1] instead of an APU (and hopefully in such a case it also? doesn't do anything). Nil Einne (talk) 14:45, 14 April 2014 (UTC)[reply]
BTW, I couldn't really find any discussion about UMA framebuffer with a hUMA APU so this is complete speculation. If it does have an effect, perhaps it doesn't affect what's available to the CPU (or perhaps it does), but what it does affect is what's available to non hUMA compatible programs using the GPU part of the APU. I'm not sure what memory is available in such case, it could be the entirety of the system RAM or some subset thereof for applications using older librarys which only support 32 bit GPU memory addressing. But it could be that this risks problems so instead a certain amount of reserved or unreserved memory is assigned for this purpose. (One problem may be if a very poorly coded program uses significantly more GPU memory than it needs because it's there. On the other hand, setting this in the UEFI or BIOS seems unnecessary since it could be done in the driver, probably even on a per application basis.) There's also the issue of legacy access to the GPU some of which is probably still supported for compatibility reasons and which won't understand the concept of hUMA. Nil Einne (talk) 18:42, 14 April 2014 (UTC)[reply]

psu wiring

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I have a headphone amp, which I had to replace the transformer , it has a dual secondary toroid , 0-15-0-15, and 4 rectifier terminals which are Ac-15, Ac-Ground(zero), Ac-15, Ac-Ground.

So, I gathered it would have 0 -15 to the first pair(ie Ac-15-Ac-0) and same for the second, the order wouldn't matter. When opened though the trans turned out to be hooked up in a different fashion instead it had one pair of each of the 15volts wires out of the two secondaries separately connected to the two AC15 terminals,(as it should) but each of the secondary 0s were linked together (twisted) and stuck to just one of the 0v terminals. Does this way of wiring have some particular application ,maybe lesser hum or other benefits ? or was it rather someone's blunder and just plain wrong ? thanks — Preceding unsigned comment added by 77.35.1.84 (talk) 14:35, 14 April 2014 (UTC)[reply]

It's possible that this wiring was deliberate to avoid an earth loop. I'm not sure what the configuration of your transformer and rectifier is, so I can't comment of whether the practice is "plain wrong". Dbfirs 20:56, 15 April 2014 (UTC)[reply]

Printer problem not printing from a specific PC

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Here at my job I have this this:

PC1=PC With windows XP OS

PC2=PC with windows XP OS

Epson= Printer connected to PC1 by USB and shared to other pcs by network

RICOH=Printer connected by modem with network cable


Something strange is happening here. From PC2 I can print using ricoh and Epson and with PC1 can only print with epson.

So PC2 can see ricoh but PC1 cant, and PC1 network is working since it can use internet and share the printer.
What can be the problem?201.78.176.96 (talk) 18:32, 14 April 2014 (UTC)[reply]

More details? 123chess456 (talk) 01:07, 15 April 2014 (UTC)[reply]
What O/S ? If it' a Microsoft network, those seem to randomly drop devices and add them back in, maybe based on boot order. StuRat (talk) 02:08, 15 April 2014 (UTC)[reply]
Both computers have XP OS. PC 1 can go to a webpage like thing where you can edit the configs of the ricoh printer, but cant find the printer on network (but when you go add printer windows thing, it can find the name of the "computer" this printer is on (8000 is the name of this "computer" and inside this would be the printer with name ricoh 8000...). PC1 was able to print with this RICOH printer until 5 days ago. 201.78.176.96 (talk) 12:07, 15 April 2014 (UTC)[reply]
Are both printers properly defined as network printers ? StuRat (talk) 13:48, 15 April 2014 (UTC)[reply]