Hi! I have had the exactly the same problem, with the following hard/software properties:
Version: 0.10.251 64 bit http://cuda-z.sf.net/ 1
OS Version: Windows x86 6.2.9200
Driver Version: 425.91
Driver Dll Version: 10.10 (25.21.14.2591)
Runtime Dll Version: 6.50

Core Information
Name: Quadro K2100M
Compute Capability: 3.0
Clock Rate: 666.5 MHz
PCI Location: 0:1:0
Multiprocessors: 3 (576 Cores)
Threads Per Multiproc.: 2048
Warp Size: 32
Regs Per Block: 65536
Threads Per Block: 1024
Threads Dimensions: 1024 x 1024 x 64
Grid Dimensions: 2147483647 x 65535 x 65535
Watchdog Enabled: Yes
Integrated GPU: No
Concurrent Kernels: Yes
Compute Mode: Default
Stream Priorities: No

…
(as reported by cuda-z).
What I did, was the following: I uninstalled all previous attempts to install CUDA for pytorch -and - simply copied your ‘pip install’ string in windows shell. After the installation, I again copied
>>> import torch
>>> torch.cuda.is_available()

and - obtained True!
What is then the difference between you case and mine?