Please help me with a new machine build

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Message 1860847 - Posted: 10 Apr 2017, 23:56:34 UTC - in response to Message 1860770.  

OK, so I did a little research on dual channel RAM and it seems that one way to get a viable 24 GB solution would be:

2 of these: (2 x 8 GB)
https://playit.de/crucial-ballistix-sport-lt-udimm-8gb-ddr4-2400-cl16.html

and this dual channel kit (2 x 4 GB):
https://www.cyberport.at/form/?DEEP=2410-16U&APID=294&STOREID=7

If installed correctly (12 GB in one channel and 12 GB in the other), this should give full speed across all of the 24 GB, right?

The math would work out as 16 Gb in one channel and 8Gb in the other channel. Still it is never a good idea to mix memory capacities. All the same type in either one channel, dual channel or quad channel. Since Kaby Lake is dual channel only, either go with two sticks or 4 sticks of the same memory density. That means 2 X 16 GB sticks or 4 x 8 GB sitcks for 32 GB total. Or just go for a total of 16GB. I have never been able to figure out just why anyone needs 32 GB of memory unless it is a server class machine and that would be on the low end of memory. I have no familiarity with any typical desktop or productivity applications that use that much memory. BOINC normally uses less than 2 GB of memory. I believe the recommended minimum for Windows is 4 GB and at least 8 GB preferred. 16 GB seems to be the common capacity for Windows of any modern flavor.


If he puts a 4Gb and 8GB stick in each channel there's no problem here. 12GB in each channel. I've seen people make the claim that it's not a good idea to mix different sticks in the same channel but I've never seen any evidence that this causes problems. Also even if he did it "wrong" and put the two 8GB sticks in the first channel slots and the two 4GB sticks in the second channel slot it would operate in flex mode and he would get dual channel for the first 8GB in each channel and then single channel speed for the final 8GB in the first channel.

http://www.intel.com/content/www/us/en/support/boards-and-kits/000005657.html#flex
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Message 1860857 - Posted: 11 Apr 2017, 0:30:27 UTC - in response to Message 1860766.  

OK, so I did a little research on dual channel RAM and it seems that one way to get a viable 24 GB solution would be:

2 of these: (2 x 8 GB)
https://playit.de/crucial-ballistix-sport-lt-udimm-8gb-ddr4-2400-cl16.html

and this dual channel kit (2 x 4 GB):
https://www.cyberport.at/form/?DEEP=2410-16U&APID=294&STOREID=7

If installed correctly (12 GB in one channel and 12 GB in the other), this should give full speed across all of the 24 GB, right?


. . That's the way I understand it, but it's important to make sure the RAM is all coherent, ie same speed and latency and preferably same manufacturer. Those all seem to be suitable.

Stephen

:)
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Message 1860859 - Posted: 11 Apr 2017, 0:49:27 UTC - in response to Message 1860770.  

OK, so I did a little research on dual channel RAM and it seems that one way to get a viable 24 GB solution would be:

2 of these: (2 x 8 GB)
https://playit.de/crucial-ballistix-sport-lt-udimm-8gb-ddr4-2400-cl16.html

and this dual channel kit (2 x 4 GB):
https://www.cyberport.at/form/?DEEP=2410-16U&APID=294&STOREID=7

If installed correctly (12 GB in one channel and 12 GB in the other), this should give full speed across all of the 24 GB, right?

The math would work out as 16 Gb in one channel and 8Gb in the other channel. Still it is never a good idea to mix memory capacities. All the same type in either one channel, dual channel or quad channel. Since Kaby Lake is dual channel only, either go with two sticks or 4 sticks of the same memory density. That means 2 X 16 GB sticks or 4 x 8 GB sitcks for 32 GB total. Or just go for a total of 16GB. I have never been able to figure out just why anyone needs 32 GB of memory unless it is a server class machine and that would be on the low end of memory. I have no familiarity with any typical desktop or productivity applications that use that much memory. BOINC normally uses less than 2 GB of memory. I believe the recommended minimum for Windows is 4 GB and at least 8 GB preferred. 16 GB seems to be the common capacity for Windows of any modern flavor.


. . Sorry but that is not the way I understand it (see diagram). Same all round is fine, but his way works AOK. In my Core2 Duo I have 2 x 2Gb and 2 x 1GB and running just fine thank you very much. The most critical consideration is that each bank has totally coherent ram, same size, same speed, same latency, preferably same manufacturer. But the next priority is to have the same speed and latency across all banks.

			Chan 0			Chan 1

	Bank 0		 _________		 _________
			|	  | 	        |         |
               Slot 0   |__8GB____|    Slot 2   |__8 GB___|

	Bank 1           _________               _________
		        |         |             |         |
	       Slot1    |__4GB____|    Slot 3   |__4 GB___|

                           12 GB                   12 GB


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Message 1860860 - Posted: 11 Apr 2017, 0:51:57 UTC - in response to Message 1860847.  
Last modified: 11 Apr 2017, 1:04:24 UTC

OK, so I did a little research on dual channel RAM and it seems that one way to get a viable 24 GB solution would be:

2 of these: (2 x 8 GB)
https://playit.de/crucial-ballistix-sport-lt-udimm-8gb-ddr4-2400-cl16.html

and this dual channel kit (2 x 4 GB):
https://www.cyberport.at/form/?DEEP=2410-16U&APID=294&STOREID=7

If installed correctly (12 GB in one channel and 12 GB in the other), this should give full speed across all of the 24 GB, right?

The math would work out as 16 Gb in one channel and 8Gb in the other channel. Still it is never a good idea to mix memory capacities. All the same type in either one channel, dual channel or quad channel. Since Kaby Lake is dual channel only, either go with two sticks or 4 sticks of the same memory density. That means 2 X 16 GB sticks or 4 x 8 GB sitcks for 32 GB total. Or just go for a total of 16GB. I have never been able to figure out just why anyone needs 32 GB of memory unless it is a server class machine and that would be on the low end of memory. I have no familiarity with any typical desktop or productivity applications that use that much memory. BOINC normally uses less than 2 GB of memory. I believe the recommended minimum for Windows is 4 GB and at least 8 GB preferred. 16 GB seems to be the common capacity for Windows of any modern flavor.


If he puts a 4Gb and 8GB stick in each channel there's no problem here. 12GB in each channel. I've seen people make the claim that it's not a good idea to mix different sticks in the same channel but I've never seen any evidence that this causes problems. Also even if he did it "wrong" and put the two 8GB sticks in the first channel slots and the two 4GB sticks in the second channel slot it would operate in flex mode and he would get dual channel for the first 8GB in each channel and then single channel speed for the final 8GB in the first channel.

http://www.intel.com/content/www/us/en/support/boards-and-kits/000005657.html#flex

The same article shows configuration for best performance under Dual-channel with four DIMMs.



Where the first group is populated with one size and the second group is populated with another size.
In Intel's example they used a pair of 4GB and 2GB DIMMs for 12GB.

My personal preference would be to go with 32GB (2x16GB DDR4-2400). That leaves the system open to be maxed at 64GB later if need be.
Going with 4x8GB could be more a more cost effective way to run DDR4-2400 over DDR4-2133.


For the CPU cooler the stock Intel ones are not ideal for 24/7 crunching. The environment the machine operates in is really the deciding factor. The cooler can always be upgraded later if required.
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Message 1860864 - Posted: 11 Apr 2017, 1:05:49 UTC - in response to Message 1860789.  

Yes, and another one at x4. According to a graph in this article, there is no substantial downside to running a GTX 680 in a PCIe 3.0 x4 slot:
http://www.tomshardware.co.uk/forum/386054-33-would-pcie-slot-bottleneck

When it comes to crunching, 5% becomes 'substantial over time. A more modern mobo with 2x PCIe x16 slots wouldn't mean all that much $$$ in the greater scheme of your build, imho.


. . That would be true if the PCIe bus were to be driven at anything near full capacity. Crunching only uses a small fraction of the bus capacity, and I doubt you would be able to even measure any difference in productivity between the two.

. . I have 2 x GTX1060s running in two PCIe 1.1 slots at x 8, and they barely make a blip on the bus usage, lurking down about the 10 to 12% area.

Stephen

:)
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Message 1860868 - Posted: 11 Apr 2017, 1:11:44 UTC - in response to Message 1860859.  

OK, so I did a little research on dual channel RAM and it seems that one way to get a viable 24 GB solution would be:

2 of these: (2 x 8 GB)
https://playit.de/crucial-ballistix-sport-lt-udimm-8gb-ddr4-2400-cl16.html

and this dual channel kit (2 x 4 GB):
https://www.cyberport.at/form/?DEEP=2410-16U&APID=294&STOREID=7

If installed correctly (12 GB in one channel and 12 GB in the other), this should give full speed across all of the 24 GB, right?

The math would work out as 16 Gb in one channel and 8Gb in the other channel. Still it is never a good idea to mix memory capacities. All the same type in either one channel, dual channel or quad channel. Since Kaby Lake is dual channel only, either go with two sticks or 4 sticks of the same memory density. That means 2 X 16 GB sticks or 4 x 8 GB sitcks for 32 GB total. Or just go for a total of 16GB. I have never been able to figure out just why anyone needs 32 GB of memory unless it is a server class machine and that would be on the low end of memory. I have no familiarity with any typical desktop or productivity applications that use that much memory. BOINC normally uses less than 2 GB of memory. I believe the recommended minimum for Windows is 4 GB and at least 8 GB preferred. 16 GB seems to be the common capacity for Windows of any modern flavor.


. . Sorry but that is not the way I understand it (see diagram). Same all round is fine, but his way works AOK. In my Core2 Duo I have 2 x 2Gb and 2 x 1GB and running just fine thank you very much. The most critical consideration is that each bank has totally coherent ram, same size, same speed, same latency, preferably same manufacturer. But the next priority is to have the same speed and latency across all banks.

			Chan 0			Chan 1

	Bank 0		 _________		 _________
			|	  | 	        |         |
               Slot 0   |__8GB____|    Slot 2   |__8 GB___|

	Bank 1           _________               _________
		        |         |             |         |
	       Slot1    |__4GB____|    Slot 3   |__4 GB___|

                           12 GB                   12 GB



I would have modified the diagram slightly with the labels
Bank0 = 16GB
Bank1 = 8GB
Since it is less common to provide a total for each channel.
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Message 1860869 - Posted: 11 Apr 2017, 1:14:09 UTC - in response to Message 1860789.  

Yes, and another one at x4. According to a graph in this article, there is no substantial downside to running a GTX 680 in a PCIe 3.0 x4 slot:
http://www.tomshardware.co.uk/forum/386054-33-would-pcie-slot-bottleneck

When it comes to crunching, 5% becomes 'substantial over time. A more modern mobo with 2x PCIe x16 slots wouldn't mean all that much $$$ in the greater scheme of your build, imho.

Over the years of using multi GPU's on x16, x8 and x4 PCI-e slots I have never seen any differences in crunching times between them, gaming is a totally different story to crunching SETI.

Cheers.
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Message 1860875 - Posted: 11 Apr 2017, 1:59:25 UTC - in response to Message 1860869.  


Over the years of using multi GPU's on x16, x8 and x4 PCI-e slots I have never seen any differences in crunching times between them, gaming is a totally different story to crunching SETI.

Cheers.


Actually, I have seen the difference. The problem, or rather the solution, is that we have really good optimized apps here at Seti (tips hat to the developers)
On other projects where the apps aren't as well optimized, you can see a huge difference in processing data depending on the PCI-e speed.
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Message 1860876 - Posted: 11 Apr 2017, 2:04:07 UTC - in response to Message 1860864.  



. . That would be true if the PCIe bus were to be driven at anything near full capacity. Crunching only uses a small fraction of the bus capacity, and I doubt you would be able to even measure any difference in productivity between the two.

. . I have 2 x GTX1060s running in two PCIe 1.1 slots at x 8, and they barely make a blip on the bus usage, lurking down about the 10 to 12% area.

Stephen

:)


Is this on your Linux system? If so, aren't you only running 1 at a time? I only ask as windows users tend to run more than 1 at a time and the tuning can increase that FB usage. I mention this as one of my teammates spend alot time finding the tuning commonly used now. We are off topic again, apologies to the OP.
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Message 1860879 - Posted: 11 Apr 2017, 2:48:38 UTC

... and occasional HD or even 4K video editing
I would look at the specs for this to answer your 24/32MB question.

That is where you will want more memory IMO.
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Message 1860885 - Posted: 11 Apr 2017, 5:08:09 UTC - in response to Message 1860876.  

Running the Perti/Tbar special app you only run one at a time. It is designed to use all available to core to the max, unlike the SoG and older offerings which only use the number of cores needed and that is often below 50% - hence running two at a time under Windows or Linux when running older apps.
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Message 1861216 - Posted: 13 Apr 2017, 14:35:18 UTC

Thank you all for your answers. Based on your answers, I chose the following options:

MB, CPU, GPU as posted intially
The € 35 CPU fan (designed for up to 140W TDP)
16 GB of DDR4-2400 RAM. If I need more, I can upgrade to 24 or 32 GB later.
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Message boards : Number crunching : Please help me with a new machine build


 
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