Below is what I found in SQL Logs:

Current time is 11:21:33 07/17/15.                                                                               

=====================================================================                                           

       Bug Check Dump                                                                                             

=====================================================================                                                                                                                                   

This file is generated by Microsoft SQL Server                                                                  

version 10.50.6000.34                                                                                           

upon detection of fatal unexpected error. Please return this file,                                              

the query or program that produced the bug check, the database and                                               

the error log, and any other pertinent information with a Service Request.                                      

                                                                                                                                                                                                                           

Computer type is Intel(R) Xeon(R) CPU E5-2650 0 @ 2.00GHz.                                                      

Bios Version is DELL   - 1                                                                                      

Phoenix ROM BIOS PLUS Version 1.10 1.4.8                                                                        

16 X64 level 8664, 1 Mhz processor (s).                                                                         

Windows NT 6.1 Build 7601 CSD Service Pack 1.                                                                   

                                 

Memory                               

MemoryLoad = 82%                    

Total Physical = 196562 MB          

Available Physical = 34476 MB       

Total Page File = 227280 MB         

Available Page File = 63505 MB      

Total Virtual = 8388607 MB          

Available Virtual = 8183173 MB      

***Unable to get thread context for spid 0                                                                      

* *******************************************************************************                                

*                                                                                                               

* BEGIN STACK DUMP:                                                                                             

*   07/17/15 11:21:33 spid 1540                                                                                 

*                                                                                                               

* Non-yielding Scheduler                                                                                         

*                                                                                                               

* *******************************************************************************            

what i read from below link is 

https://support.microsoft.com/en-us/kb/2699013

 to apply latest SP or Cumulative Update package 1 for SQL Server 2008 R2 Service Pack 2   

 

but what my server have is    

Current version: SQL Server 2008 R2, SP3 (Enterprise Edition (64-bit))

Current build number: 10.50.6000

but i have found in online forums below,

 I just want to make sure i am downloading the correct one  below;

https://support.microsoft.com/en-us/kb/3033860

 The build number of the hotfix update package is 10.50.6525.0.

please let me know ...

• Moved by Naomi N 9 hours 37 minutes ago May be a better forum (or SQL DB Engine)

If you already have SP3, you don't need SP2. It may be better to wait for response from MS people on this forum or better in another forum I'm going to move this thread to as this has nothing to do with T-SQL.

sorry about posting in wrong window, anyways i found the solution 

I have 

Current version: SQL Server 2008 R2, SP3 (Enterprise Edition (64-bit))

Current build number: 10.50.6000

 I will have to apply latest Cumulative update to fix the issue, info is below link.

https://support.microsoft.com/en-us/kb/3033860

 The build number of the hotfix update package is 10.50.6525.0.

 

• Proposed as answer by Naomi N 9 hours 8 minutes ago

Nick,

I guess you are correct Non yielding schedulers are basically code bugs in SQL Server which MS fixes in there SP and CU release so applying latest CU after SP3 (10.50.6525.0.)would help.