Best options for my system and true syntx

[krackthehash]

Hello everybody,
I would kindly want to ask best options for my hardware listed below for a single hash (password should be 6-15 numerics(digits) ONLY) and what is the complete command i should use for brute force attack with resume option enabled only.
Thank you very much.
Specs:
SiSoftware Sandra

Total Memory : 2.64GB DDR3 SO-DIMM

Processors
Processor : Intel(R) Core(TM) i7-3632QM CPU @ 2.20GHz (4C 8T 3.09GHz, 3.1GHz IMC, 4x 256kB L2, 6MB L3)
Socket/Slot : FC PGA988

Chipset
Memory Controller : HP ProBook 4540s 100MHz, 2x 3GB DDR3 SO-DIMM 1.6GHz 128-bit, Integrated Graphics

Memory Module(s)
Memory Module : Samsung M471B5773DH0-CK0 2GB DDR3 SO-DIMM PC3-12800S DDR3-1600 (11-11-11-29 5-40-13-6)
Memory Module : Hynix (Hyundai) HMT351S6CFR8C-PB 4GB DDR3 SO-DIMM PC3-12800S DDR3-1600 (11-11-11-29 5-40-13-6)

Video System
Monitor/Panel : LGD Generic PnP Monitor (1600x1200, 15.3")
Video Adapter : Intel(R) HD Graphics 4000 (16CU 128SP SM5.0 350MHz/1.15GHz, 2GB DDR3 1.6GHz 128-bit, Integrated Graphics)

Graphics Processor
OpenCL GP Processor : AMD Radeon HD 7650M (480SP 6C 500MHz, 2GB)
Compute Shader Processor : Intel(R) HD Graphics 4000 (128SP 16C 350MHz/1.15GHz, 2GB DDR3 1.6GHz/1.8GHz 128-bit, Integrated Graphics)



Operating System
Windows System : Microsoft Windows 7 Ultimate 6.01.7601 (Service Pack 1)
Platform Compliance : x86