lucaskclai :
Dear Janpieter,
GTX Titan 6 GB GDDR5 in Hong Kong is HK$9,900.00/pc while GTX Titan 2 GB is only HK$975.00.
can you give me the model number of the 2GB and 6GB version? something here does not feel right
lucaskclai :
I take it you agree with the motherboard ASUS P9x79 WS Deluxe and can only put 4 GTX. Your suggestion is asus Z9PE if I go for 2 CPU. How much faster do you think I can get for 2 CPU on top of your estimataion 8 T FLOPS. I like to know from investment point of view. At this stage, this new PC would not be cheap. Despite I do not have a budget for this machine for my research but I like to get the best from the money. Your suggestion is really appreciated.
as I already said: if you have 4 geforce GTX titan cards which render your floating-point mathematics, a 2nd CPU is not worth it. you could use it for cases where the GPUs cannot be used, though. the openCL implementation in MATLAB is not complete. You said you also know how to program in C. If you have a number of routine-algorithms, it will be better to take them out of matlab and recreate them in pure openCL, as it may be faster in some cases.
lucaskclai :
Yes, you are correct to use RAID-0 for I/O as I can combine 4 to 6 T hard drive. I do not know how to do the cooling system in RAID-0. I understand GTX already have cooling system.
you will need to design your own cooling system: if you have
- 2 xeon CPUs (260W)
- 4 GTX titans (1000W)
- 4 HDD (90W)
- mainboard + additional loss (fans, dvd, leds, usb devices, etc) (50W)
you have a system which will produce 1400W of heat at full load. you can not do this with air cooling in any way: there's no way you can push enough air through your case to cool down all these components.
you will have to:
- install waterblocks on the GTX titans
- install waterblocks on the Xeon CPUs
- buy a large external radiator with a large number of fans, and connect all those waterblocks to the radiators
- divide the HDDs so not all 4 of them are mounted next to each other. a 5.25" -> 3.5" mounting case may help here
- search for a power supply which is capable of handling this amount of power. also note that they degenerate and not everything is heat, so 1400W will not be enough: 1500W is close, but I'd recommend looking for a 1600W.
*edit*: forgot to add: if you are using more than 3 disks in a raid-0, better add an extra spare for ECC and jump to raid 5. I know it has a performance penalty, but with 6 disks in a raid-0 chances of losing data are quite high.