diff --git a/stepmania/src/RageDisplay.cpp b/stepmania/src/RageDisplay.cpp
index b032c37861..b2b2de967a 100644
--- a/stepmania/src/RageDisplay.cpp
+++ b/stepmania/src/RageDisplay.cpp
@@ -101,9 +101,14 @@ RageDisplay::RageDisplay( bool windowed, int width, int height, int bpp, int rat
 	glGetFloatv(GL_POINT_SIZE_GRANULARITY, &m_oglspecs->point_granularity);
 	LOG->Info("Point size range: %f-%f +%f", m_oglspecs->point_range[0], m_oglspecs->point_range[1], m_oglspecs->point_granularity);
 
-	m_oglspecs->bAALinesCauseProblems = strncmp((const char*)glGetString(GL_RENDERER),"3Dfx/Voodoo3 (tm)/2 TMUs/16 MB SDRAM/ICD (Nov  2 2000)",sizeof("3Dfx/Voodoo3"))==0;
+	/* sizeof("string constant") is the size of the pointer (~4), not the length of the string. */
+	m_oglspecs->bAALinesCauseProblems = strncmp((const char*)glGetString(GL_RENDERER),"3Dfx/Voodoo3 (tm)/2 TMUs/16 MB SDRAM/ICD (Nov  2 2000)",strlen("3Dfx/Voodoo3"))==0;
 	if( m_oglspecs->bAALinesCauseProblems )
 		LOG->Info("Anti-aliased lines are known to cause problems with this driver.");
+	m_oglspecs->bPackedPixelsCauseProblems = 
+	    strncmp((const char*)glGetString(GL_RENDERER),"GLDirect",strlen("GLDirect"))==0;
+	if( m_oglspecs->bPackedPixelsCauseProblems )
+		LOG->Info("Packed pixel formats are known to cause problems with this driver.");
 }
 
 bool RageDisplay::IsSoftwareRenderer()
diff --git a/stepmania/src/RageDisplayInternal.h b/stepmania/src/RageDisplayInternal.h
index 07405269b6..eb36f41c23 100644
--- a/stepmania/src/RageDisplayInternal.h
+++ b/stepmania/src/RageDisplayInternal.h
@@ -47,6 +47,9 @@ struct oglspecs_t {
 
 	/* Is AA known to cause problems in this driver? (Voodoo3) */
 	bool bAALinesCauseProblems;
+
+	/* Packed pixel data types don't work in GLDirect. */
+	bool bPackedPixelsCauseProblems;
 };
 
 /* Extension functions we use.  Put these in a namespace instead of in oglspecs_t,