According https://confluence.atlassian.com/adminjiraserver071/connecting-jira-applications-to-sql-server-2012-802592195.html JIRA 7 supports the following collations with SQL Server 2012:

Collation type must be case-insensitive. We support 'SQL_Latin1_General_CP437_CI_AI' and 'Latin1_General_CI_AI' as case-insensitive, accent-insensitive, and language neutral collation types. If your SQL Server installation's collation type settings have not been changed from their defaults, check the collation type settings.

The JIRA Instance Health says: Result OK
with Message: The database collation 'Latin1_General_CI_AI' and table collation 'Latin1_General_CI_AI' are supported by JIRA.

But in the atlassian-jira.log the following WARN message is logged:

2016-03-24 10:45:50,754 JIRA-Bootstrap WARN [c.a.j.appconsistency.db.CollationCheck]

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You are using an unsupported mssql collation: Latin1_General_CI_AI. This may cause some functionality to not work.
Please use SQL_Latin1_General_CI_AI or SQL_Latin1_General_CP437_CI_AI as the collation instead.
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