HD 5850 Flickering

Just installed a Sapphire 5850 in my brother's computer, hooked up all good. No overclocking as he doesn't game at all.

Worked well for about a day then the screen would flicker randomly after being turned on, cursor would appear 10x bigger. One monitor is plugged into the DVI port and a TV into the HDMI port. The TV is perfectly fine but only the monitor is flickering.

Only thing that would fix it was messing with the resolution in CCC until it would stop, any ideas?

Edit: Oh and it's hooked up to a 700w PSU so it should be good for power.

those are alot of symptoms mentioned by a lot of people. Have you tried the latest drivers. ATI has not completely fixed these problems, but I would think they tried some things. The flickering and huge mouse pointer are definitely common gripes. I hear going in to CCC and overdrive, try changing the settings for memory and gpu speed, down by 50. Heard that works for some. Maybe the card hunts for power states ?

ATI Confirms 5700, 5800 Problems; Promises Fix
http://www.tomshardware.com/news/A [...] ,9549.html

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I get flickering with my 5870 when adjusting the OC settings in CCC, whether I decrease or increase the settings on the GPU or Memory clock by even 1mhz. But runs perfectly fine when left alone at stock settings. Just buggy drivers. Some cards experience it... others don't. Sometimes doing a Driver Sweep and reinstall drivers will work. If that doesn't work, your options may be to wait for 10.2 catalyst drivers (good lord I hope they come soon lol) or RMA the card and hope for the best.

If you run two monitors with existing drivers from ATI, and use ATI Overdrive to set the timings to anything other than stock, the idle clocks will be set too low to run two monitors. One monitor flickers, while the other is fine.

My guess is that your brother decided to fool around with ATI Overdrive.

Use Catalyst 9.12 Hotfix and drop a monitor if possible. I'm running one monitor and 9.12 hotfix and it works great. There seem to be some major issues with dual monitors at this point and and 10.1 drivers are a joke (break more than they fix).

Well I didn't change anything, but we changed the monitor that was in use. Couldn't have been the monitor since there was no problem before we switched to the 5850 from a Nvidia 210. But no flickering to my knowledge since I don't actually use the computer. Though I think there is still the huge cursor. I'll check out that hotfix. Thanks.