Is there another PC with a regular DVI to test DVI to DVI? We do not test on DP to DVI adapters.

No, I've only got the one computer.  Nearly all Macs are Mini DisplayPort only these days, so it would be interesting to know how else I and other Mac users should connect to the monitor.  Or is the screen actually not Mac-compatible?

Any other suggestions?

Thanks.

I've noted the forum post from Dell stating that none of Dell's monitors are validated for use with Macs.  A bit disappointing, since the U2311H appears to be aimed at creative usage, a market sector with relatively high Mac representation. Given that plenty of Mac users are buying Dell products, it would be nice not to feel totally unsupported by Dell.

This isn't a great fix, but if anyone else is experiencing a similar issue, I've noticed significant improvement by selecting Custom RGB profile and nudging the blue and green down 4-5 points.  The screen takes on a pinkish tinge, but the pinstriping becomes a lot less noticeable.

If this workaround suggests any more satisfactory fixes to Dell representatives, or if it sounds symptomatic of a known issue, I'd be interested to have some further help.

Let me chine in and say I also have this problem and not only with the u2311h but with an apple cinema 20"  dvi display.   I don't believe its the monitor,  my theory is  that its' Snow Leopard. Certain users say  using a display port video card alleviates this issue.   I didnt have this problem with leopard 10.5.8  but I believe started happening with 10.6.4 combo update.    It also doesnt happen when using a dvi to VGA adapter.

Also let me explain another reason why I dont believe the monitor is at fault.  Connected to a windows 7 running PC it exhibits none of this behavior either.  So the problem is the software not the hardware. Make sense?   I believe apple royally messeed up the latest snow leopard not only with this issue but overall OPENGL performance on nvidia based cards.

I need to perform more tests. But like you i am seeing vertical pinstripes on certain solid colors.   So if you have the option try an earlier version pre 10.6.4 or leopard.   Which version of OSX are you running?

Thanks wojowork that's helpful.  I'm on 10.6.4 as well.  I might try a mini-displayport-to-HDMI adapter/cable and see if that helps.  Have you tried installing Windows on your Mac with Boot Camp; that would eliminate all hardware issues?  That's the next thing I'm planning to try when I have a couple of hours spare.

Well if running windows is your plan then it might work without the vertical pinstriping.    But I havent tried bootcamp.  I hooked it up to a pc.    It should work the same in theory.    I want to run OSX ! Hopefully all of this gets sorted by 10.6.5  

Yeah, fingers crossed for 10.6.5 (ha ha)!  I have no desire to run Windows, just thought that if the problem disappeared under bootcamp/windows, then that would confirm your hunch that the issue is a straightforward OSX hitch.

10.6.5 the issue persists lol  oh well

Have any of you managed to get this monitor working with a mini-display port to display port adapter cable?  If only I hadn't of been so rash, If I'd of read this forum sooner there is no way I would have purchased the U2311H.  Still if it works with with the display port route I'd be happy.