On Thu, May 31, 2012 at 8:36 AM, William Brent <span dir="ltr">&lt;<a href="mailto:william.brent@gmail.com" target="_blank">william.brent@gmail.com</a>&gt;</span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Thanks Chris &amp; Cyrille.  I don&#39;t have an nvidia GPU, so I&#39;ll see what I can find in the Xorg.conf.  For totally digital displays, how does the refresh rate come into play?  I&#39;m seeing out there that VBL doesn&#39;t apply to digital.</blockquote>
<div><br></div><div>The refresh rate for LCD is 60Hz although internally many process at 120 or even higher.</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div></div><div>I tried single buffer mode with each metro tick banging the gemhead and then clearing the gemwin, but got jittery results with the video stream.  </div></blockquote><div><br></div><div>Without syncing to the refresh rate the video display will be jittery and also have tearing artifacts.  As Cyrille points out there are ways to run gemheads at higher speeds, but you want to keep all of the drawing objects at refresh rate.</div>
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