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Wikipedia:Reference desk/Archives/Computing/2015 September 1

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September 1

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Workstation memory question

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If a workstation can take two physical CPUs (each may have multiple cores), and it has eight memory slots (two groups of four), does each group of four memory slots serve one CPU? Or if there is only one CPU installed, can it use memory in all eight slots? Bubba73 You talkin' to me? 01:04, 1 September 2015 (UTC)[reply]

Memory is used by the operating system. It is allocated as needed by the operating system. It is not reserved based on physical location on the motherboard. — Preceding unsigned comment added by 75.139.70.50 (talk) 01:32, 1 September 2015 (UTC)[reply]
Have you read our article on Non-uniform memory access? Nil Einne (talk) 11:27, 1 September 2015 (UTC)[reply]
Non-uniform memory access (NUMA) is similar to what the question is asking. However, it is still limited by the first answer here. The operating system (OS) decides what memory is used for which processor. It has the option to choose any location in memory to reserve for a process. With NUMA, the hardware offers memory that is physically closer (based on wire length) to each CPU. The OS has the option to pay attention to NUMA and reserve memory that is optimized for the processor. However, it can ignore NUMA. So, it is not a case that if you have 2 processors and 2 sticks of RAM, each CPU uses one stick. Both CPUs use both sticks. The OS handles the management of exactly what parts of memory are being used. 209.149.113.150 (talk) 13:14, 1 September 2015 (UTC)[reply]
But the article seemed to explain all that when I read it. It didn't mention what DF said so that's an important point, although that follows logically from IMCs. Nil Einne (talk) 13:07, 3 September 2015 (UTC)[reply]
If both CPUs are populated, either CPU can use memory from either set. There will be somewhat different latencies, depending on the physical location of the memory as explained by NUMA above. If only one CPU is populated, then in most cases the motherboard will NOT support any memory that is placed adjacent to the empty CPU slot. Refer to the motherboard documentation to be sure. Dragons flight (talk) 21:07, 2 September 2015 (UTC)[reply]
That is what I suspected. There are two CPU sockets, four memory slots near one and four near the other one. I was wondering what happens if there is only one CPU installed. I'm looking a a Dell Precision workstation, so I don't know the motherboard maker. But maybe I can find it in the user's guide. Bubba73 You talkin' to me? 04:15, 5 September 2015 (UTC)[reply]
I suspect the motherboard isn't going to make a difference here. If it's a Dell Precision workstation and a recent one, I'm guessing it has some sort of recent Intel Xeon with an IMC. If it uses IMC, it's fairly unlikely the memory will work without the CPU since there will be no memory controller, so it would need a fairly specialised set-up for the memory to work. Nil Einne (talk) 16:47, 5 September 2015 (UTC)[reply]
Yes, it does use Xeon(s). Bubba73 You talkin' to me? 19:52, 5 September 2015 (UTC)[reply]

Where's OK Google?

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I'm new to smart phones and love "OK Google" on my android Galaxy S6. All of a sudden... it's gone! Previously it would come up on the start screen, but now it doesn't. How could I lose it? How can I get it back? --Halcatalyst (talk) 03:28, 1 September 2015 (UTC)[reply]

Dunno how you accidentally nuked it - but it should be easy to put back. Tap the circle with the six dots that represents the Apps & Widgets library. Tap on the "Widgets" tab, then swipe sideways until you see "Google App" - touch and hold the icon - then you can drag it onto whichever screen you want it on. SteveBaker (talk) 05:51, 1 September 2015 (UTC)[reply]
The path I had to take was not this one, and it took a lot of time and effort, but I got to an app called simply "Google." When I installed it, a wonderland unfolded, a huge amount of sophisticated capabilities. Not just OK Google, though I was very glad to have her back. The most phenomenal was a contact list (as large as you like) with every member represented by a big button on screen, through which you can make a phone call with two taps. --Halcatalyst (talk) 00:32, 4 September 2015 (UTC)[reply]

YouTube playlists

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Is there any way to subdivide a playlist into subchapters while still keeping it intact? 2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 10:11, 1 September 2015 (UTC)[reply]

Tracking Changes in Microsoft Word 2007

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In Word 2007, I have changed the text in a document from (say for example) "abcd" to "abcx".

The system will show the changes, even print them, in much detail. But suppose I want the system to save the document as "abcx" and forget that it used to be "abcd". In other words, how can I save a final version without saving a record of the changes?

Thank you, CBHA (talk) 23:11, 1 September 2015 (UTC)[reply]

Finalising a given change is called "accepting" the change, in Word's terms. You can accept a given change, or accept all in one go. -- Finlay McWalterTalk 23:26, 1 September 2015 (UTC)[reply]
Thank you. So once a change is accepted, the system can forget the earlier version. CBHA (talk) 23:53, 1 September 2015 (UTC)[reply]
It can be embarrassing if you forget to do this in a publicly-released document... AndrewWTaylor (talk) 07:42, 3 September 2015 (UTC)[reply]
Yes indeed it could, which is why I expected there would be a straightforward "forget-all-the-older-versions-and-save-only-the-current-version" button. ACCEPT ALL CHANGES does that but I could not find it since I was searching for something that was more front and centre obvious. CBHA (talk) 01:50, 4 September 2015 (UTC)[reply]