From e4680bbaab69e5bd9f6b022d5ae938259bfc6a24 Mon Sep 17 00:00:00 2001
From: Francis Rowe <info@gluglug.org.uk>
Date: Sat, 04 Apr 2015 14:05:59 -0400
Subject: docs/install/*_external.html: Update notes: switchable graphics

---
(limited to 'docs/install/t400_external.html')

diff --git a/docs/install/t400_external.html b/docs/install/t400_external.html
index 207e51a..e520841 100644
--- a/docs/install/t400_external.html
+++ b/docs/install/t400_external.html
@@ -54,16 +54,23 @@
 		<h1>A note about GPUs</h1>
 		
 			<p>
-				This guide currently assumes that you have an Intel GPU (non-switchable).
-				Some T400 have switchable graphics (ATI), which means that you can choose between ATI or Intel
-				in the <i>BIOS setup</i>. When switching to Intel, is lenovobios not enabling ATI
-				(where ATI is disabled by default and the system uses the Intel chip), or are they
-				disabling it (where the system uses the ATI chip by default)?
+				Some models have an Intel GPU, while others have both an ATI and an Intel GPU; this
+				is referred to as &quot;switchable graphics&quot;. In the <i>BIOS setup</i> programme
+				for lenovobios, you can specify that the system will use one or the other (but not both).
 			</p>
 			
 			<p>
-				Basically, switchable graphics is untested, but it should be easy to get it working
-				(if it doesn't already work).
+				Libreboot is known to work on systems with only the Intel GPU, using native graphics initialization.
+				On systems with switchable graphics, it is believed that the ATI chip is used by default; coreboot
+				was tested with the native init and it didn't work, so the theory is that you have to disable
+				the ATI chip and make it use the Intel GPU instead (with native graphics), using the same method
+				as lenovobios. The other alternative is to implement native graphics initialization for the ATI chip
+				used on some models, but this is much harder (disabling the ATI chip in favour of Intel is likely much easier).
+			</p>
+			
+			<p>
+				For now (unless you want to help make systems with switchable graphics work, where a display
+				is initialized for the Intel GPU), you should avoid systems with switchable graphics.
 			</p>
 			
 		<h1>CPU paste required</h1>
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