update installation instructions
diff --git a/content/docs/next/installation.html b/content/docs/next/installation.html
index f1bae8b..baf3ca7 100644
--- a/content/docs/next/installation.html
+++ b/content/docs/next/installation.html
@@ -87,12 +87,13 @@
Loading channels: done
<span class="hljs-meta">#</span><span class="bash"> Name Version Build Channel</span>
-singa 2.1.0.dev cpu_py36 nusdbsystem
-singa 2.1.0.dev cpu_py37 nusdbsystem
+singa 3.1.0.rc2 cpu_py36 nusdbsystem
+singa 3.1.0.rc2 cudnn7.6.5_cuda10.2_py36 nusdbsystem
+singa 3.1.0.rc2 cudnn7.6.5_cuda10.2_py37 nusdbsystem
</code></pre>
<!--- > Please note that using the nightly built images is not recommended except for SINGA development and testing. Using stable releases is recommended. -->
<p>The following command installs a specific version of SINGA,</p>
-<pre><code class="hljs css language-shell"><span class="hljs-meta">$</span><span class="bash"> conda install -c nusdbsystem -c conda-forge singa=X.Y.Z.dev=cpu_py37</span>
+<pre><code class="hljs css language-shell"><span class="hljs-meta">$</span><span class="bash"> conda install -c nusdbsystem -c conda-forge singa=X.Y.Z=cpu_py36</span>
</code></pre>
<p>If there is no error message from</p>
<pre><code class="hljs css language-shell"><span class="hljs-meta">$</span><span class="bash"> python -c <span class="hljs-string">"from singa import tensor"</span></span>
diff --git a/content/docs/next/installation/index.html b/content/docs/next/installation/index.html
index f1bae8b..baf3ca7 100644
--- a/content/docs/next/installation/index.html
+++ b/content/docs/next/installation/index.html
@@ -87,12 +87,13 @@
Loading channels: done
<span class="hljs-meta">#</span><span class="bash"> Name Version Build Channel</span>
-singa 2.1.0.dev cpu_py36 nusdbsystem
-singa 2.1.0.dev cpu_py37 nusdbsystem
+singa 3.1.0.rc2 cpu_py36 nusdbsystem
+singa 3.1.0.rc2 cudnn7.6.5_cuda10.2_py36 nusdbsystem
+singa 3.1.0.rc2 cudnn7.6.5_cuda10.2_py37 nusdbsystem
</code></pre>
<!--- > Please note that using the nightly built images is not recommended except for SINGA development and testing. Using stable releases is recommended. -->
<p>The following command installs a specific version of SINGA,</p>
-<pre><code class="hljs css language-shell"><span class="hljs-meta">$</span><span class="bash"> conda install -c nusdbsystem -c conda-forge singa=X.Y.Z.dev=cpu_py37</span>
+<pre><code class="hljs css language-shell"><span class="hljs-meta">$</span><span class="bash"> conda install -c nusdbsystem -c conda-forge singa=X.Y.Z=cpu_py36</span>
</code></pre>
<p>If there is no error message from</p>
<pre><code class="hljs css language-shell"><span class="hljs-meta">$</span><span class="bash"> python -c <span class="hljs-string">"from singa import tensor"</span></span>
