What are the Side Effects of Overclocking?

[exa]

How is this done?, is there a tut?

Blur Busters, being "everything better than 60Hz" (overclocking, gsync, lightboost, etc) is currently developing new overclocking tutorials that will be published in the near future.

1. Pick a favourite custom resolution utility:
NVIDIA Custom Resolution Utility (easiest, no reboot needed)
ToastyX Custom Resolution Utility (universal, need reboot)
PowerStrip Utility (for legacy systems)
2. Open the utility, set refresh rate to a higher refresh rate. Test the refresh rate.
3. Keep raising the refresh rate until it starts glitching or blacks out. Then back off.
4. Verify it works without frame skipping at http://www.testufo.com/frameskipping
5. If it isn't frame skipping, your refresh rate overclock is successful!

If you plan to overclock 1440p, you may need to unlock your drivers using http://www.monitortests.com so you're not hitting against your drivers dot clock limit. This allows you to overclock 1440p and 4K more significantly than you would otherwise, by pushing DVI cables beyond their limits. The use of Monoprice DVI cables, or other thick premium DVI cables, will help you overclock more, provided your monitor does not have a safety lock on refresh rate preventing you from overclocking.

Most displays with safety locks, won't let you overclock. But a few displays do let you easily overclock a lot (e.g. QNIX QX2710 Evolution 2, X-Star DP2710, Catleap 2B, Overlord Tempest X270OC). That said, if far less motion blur is very important, strobe backlights are superior to overclocking (LightBoost has far less motion blur than a 180Hz overclock). However, you can get improvement in motion fluidity, and far less input lag with overclocking!

When I try overclocking my monitors it does work but the resolution gets smaller or it takes the whole screen but it gets blurry, does this means that it won't work ? Or I can play with manual settings ?

[Chief Blur Buster]

When I try overclocking my monitors it does work but the resolution gets smaller or it takes the whole screen but it gets blurry, does this means that it won't work ? Or I can play with manual settings ?

Sometimes there's no side effects at all, the picture looks the same, except smoother.

Other times, side effects during display overclocking can occur. Such as one or more of the following:

-- Color degradation (reduction in contrast ratio).
-- Individual pixel response sometimes become slightly slower the quicker the LCD panel is refreshed (Less time to send voltage into LCD pixels during a faster refresh. Not all LCDs are affected by this).
-- Scan lines and strange inversion effects show up, e.g. worse at http://www.testufo.com/inversion
-- Glitching such as colored snow, colored lines, colored blocks
-- Screen fading to black or white
-- Loss of 4:4:4 chroma, going down to 4:2:2 chroma
-- Image retention issues (which disappears after displaying a blank image)
-- And finally, when out of range, the whole screen just goes black until you slow down Hz.
-- Sometimes image just gradually degrades as you're getting closer to your displays' overclocking limit.

For modern panels with very overclockable electronics (completely uncapped refresh rate), you can overclock quite a bit before any of the above. So a laptop panel that overclocks 60Hz->210Hz with some glitches, may overclock to 60Hz->180Hz with no glitches except very minor color degradation.

Editing the timings manually (Manual Timings instead of Automatic) can increase your overclock margin (by a few percent, if you decrease the Porch / Sync / Total numbers slowly until the display goes out of sync). But for the most part, just focus on raising the Hz which is much easier.

Most people can only overclock a few Hz, like 63Hz or 72Hz.
But there are ultraoverclockable panels now, with 2:1 overclocking ratios (e.g. QNIX QX2710 Evolution 2, X-Star DP2710, Catleap 2B, Overlord Tempest X270OC), for those people who prefer extra resolution over motion blur, etc.

[exa]

Thank you for the info, unfortunately only one of my screens successfully overclocked and only to 62Hz