New System Build, what should my priorities be?

[William McLaughlin]

HI:

I have not done much processing in the past year due to a tendon issue that prevents me from sitting very long. I have a pretty cool new pc "desk" system that should be here before the end of the year that hopefully will get around my medical issue and let me do more processing:

http://altwork.com/

As part of the system I plan a large 4K monitor and a new (Windows 10) PC. Here is my question:

I can go with an i7 Skylake CPU (cheaper) or a Broadwell-E (more expensive). Let us assume the same GPU for comparison. Would the greater number of cores/threads
of the Broadwell-E (lets assume a 6900-K with 8/16) vs the 4/8 of the Skylake make a large difference for PI? Just how much?

Second, how much difference would a newer GPU make - say an NVidia GTX 1080 vs an older 980 Ti make?

Bottom line - spend money on the CPU or GPU? Note I am not a gamer.

[jkmorse]

Although Juan has mentioned possibly adding GPU acceleration in the future, to date PI does not use it.  As such, as between the two I would spend the money on a faster CPU.  But your biggest bang for the buck might be to add an SSD and have your system run off of that instead of a traditional hard drive.  You can always get a big cheap hard drive as your D: drive to store all the data, but a solid state drive as your C: drive makes a huge difference.  The other place to spend money is on memory.  Get a minimum of 16Gb and 32Gb if you can afford it, then add a ramdisk.

Best,

Jim 

[William McLaughlin]

Although Juan has mentioned possibly adding GPU acceleration in the future, to date PI does not use it.  As such, as between the two I would spend the money on a faster CPU.  But your biggest bang for the buck might be to add an SSD and have your system run off of that instead of a traditional hard drive.  You can always get a big cheap hard drive as your D: drive to store all the data, but a solid state drive as your C: drive makes a huge difference.  The other place to spend money is on memory.  Get a minimum of 16Gb and 32Gb if you can afford it, then add a ramdisk.

SSD for sure, in fact I already do that with my present system. Mechanical drives have already been relegated to backups on all my systems, I could not tolerate a standard drive as a main system or often used data drive!

I plan to use two M.2 SSD on the board (one boot and programs, the other fast access data and cache). Then a couple 1Tb SSD Sata drives for main data. I already have 16 G memory and will be doing 32 on the new system - memory is cheap as is SSD space.  But then I am old and I can remember paying $400 for a 20 meg HD! 

[jkmorse]

I can top that.  I was 28 before I could afford my first computer back in 1985 and it had a whopping 16kb (Good old Atari 16k).  I had the "pleasure" of being put in charge of installing my old law firm's first word processing system.  A Wang that actually let three secretaries share one document. 

Ok now I have to stop, I'm getting depressed thinking about how old I am.   

[pfile]

Although Juan has mentioned possibly adding GPU acceleration in the future, to date PI does not use it.  As such, as between the two I would spend the money on a faster CPU.  But your biggest bang for the buck might be to add an SSD and have your system run off of that instead of a traditional hard drive.  You can always get a big cheap hard drive as your D: drive to store all the data, but a solid state drive as your C: drive makes a huge difference.  The other place to spend money is on memory.  Get a minimum of 16Gb and 32Gb if you can afford it, then add a ramdisk.

SSD for sure, in fact I already do that with my present system. Mechanical drives have already been relegated to backups on all my systems, I could not tolerate a standard drive as a main system or often used data drive!

I plan to use two M.2 SSD on the board (one boot and programs, the other fast access data and cache). Then a couple 1Tb SSD Sata drives for main data. I already have 16 G memory and will be doing 32 on the new system - memory is cheap as is SSD space.  But then I am old and I can remember paying $400 for a 20 meg HD! 

i have been thinking about building an i6700k - based system... the motherboard i was looking at apparently only has one m.2 slot. are there equivalent SSDs that just plug into a regular pcie slot or are there motherboards with multiple m.2 connectors?

thanks

rob

[William McLaughlin]

i have been thinking about building an i6700k - based system... the motherboard i was looking at apparently only has one m.2 slot. are there equivalent SSDs that just plug into a regular pcie slot or are there motherboards with multiple m.2 connectors?

There are not a lot out there, but there are some, mostly higher end as you would expect. One example:

http://www.asrock.com/mb/Intel/Z170%20Extreme7+/

You can also use an adapter card that fits a PCIe slot. An Example:

https://www.amazon.com/dp/B017JGVTAM/r

[pfile]

ah - thanks! the adapter card would probably work for me as the mobo i was looking at only has one slot. a parallel swap config with 2 m.2 cards would be insanely fast.

rob

[pfile]

i did a little reading and it seems that a lot of these boards are just sharing a PCIe slot with the m.2 slot(s), so you have to abandon the PCIe slot if you use the corresponding m.2 slot.

also the samsung m.2 cards get pretty hot and throttle themselves if they have no cooling. there is a very expensive m.2 to pcie x4 adapter that has a nice heatsink integrated with it. other people are just buying little heatsinks and attaching them to the NAND chips. apparently there's not much airflow down at the motherboard so if you use the m.2 slot the heatsinks are a must.

rob

[William McLaughlin]

also the samsung m.2 cards get pretty hot and throttle themselves if they have no cooling. there is a very expensive m.2 to pcie x4 adapter that has a nice heatsink integrated with it. other people are just buying little heatsinks and attaching them to the NAND chips. apparently there's not much airflow down at the motherboard so if you use the m.2 slot the heatsinks are a must.

Indeed. I read a review on this part a while back:

http://www.anandtech.com/show/9856/angelbird-wings-px1-m2-adapter-review-do-ssds-need-heatsinks/8

One could also go to a board that has a U.2 port as well. I don't know much about them except that they are kinda a "M.2 on a cable".

Thanks for all the replies. Based on this, I think I may lean toward a Broadwell-E system if I can find a mobo that has the other features I want. It will be another few months yet so will keep looking.