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I have the following setup:

42" LCD @ 1920x1080 connected through HDMI (using a DVI -> HDMI adapter) to a GeForce 8500GT

24" LCD @ 1920x1080 connected through DVI to a GeForce 7300GS
22" LCD @ 1680x1050 connected through VGA to the same GeForce 7300GS

When I recover from sleep mode, or when I connect a USB device such as my phone (I already have a wireless keyboard USB and wireless mouse USB connected and functioning) windows starts making that noise to indicate a device was connected and then the noise to indicate it was disconnected and all 3 screens flick on and off. It's as if they are being disconnected from the display and reconnected.

I'm wondering if there is a problem with bandwidth on the PCI bus here. Or perhaps the problem is with my video cards not being able to handle the resolutions.

Previously, the GeForce 7300GS was running

22" LCD @ 1680x1050 connected through DVI to GeForce 7300GS
19" LCD @ 1280x1024 connected through VGA to the same GeForce 7300GS

And I didn't have the flickering problem. Now that I've introduced this new screen the problem has occurred, and as you can tell, that 7300GS has to work much harder to display 1920 + 1680 wide and 1050 + 1080 tall.

Can anyone give me some advice on possible solutions? Do we think if I buy a new video card it might solve the problem?

Here's what my current setup consists of:

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Hey Guys, thanks for the comments about power. I have a 660W cooler master silent PSU. What i've done is switch around the geforce 8500 to run the dual monitor and the 7300 to run the 42" and now the problem has been solved. I won't mark this closed though just to give me a few days to test it – Jason Oct 24 '11 at 0:11
yeah, i have a monster graphics card and i run a separate 600W PSU just for it. – RobotHumans Oct 24 '11 at 2:56

Sounds like you're running a higher power consumption box than you were. I'ld look in to a bigger power supply or multi-PSU configuration.

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+1 bigger power was my first thought. – Jason Oct 24 '11 at 0:11

I think you are experiencing insufficient power for your setup. Try putting a UPS inline at the wall outlet, and that may dampen some of the brownouts. Judging from your description I would recommend at least one 1500 watt UPS.

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um, in many countries more than a 1200W won't work on a single outlet. – RobotHumans Oct 22 '11 at 1:35
+1 That's interesting, i didn't realise the outlet could be the issue. I'll look into that – Jason Oct 24 '11 at 0:11
It's not the "outlet" which is the limiting factor. It's the amount of resistance you have in series on a particular breaker. More resistance requires more amperage to maintain the voltage. Everything you plug in is a resistor (i.e. monitor, computer, etc). You could try plugging into different outlets by running extension cords across the room, but this will only help if the other outlets are on a different circuits. This would be a great time to take a look at Ohm's law. – steampowered Oct 24 '11 at 3:54

By the way you described it, I'd agree the others about the lacking in power. But I also noticed you're using a gigabyte p55-UD3R. I've had a bunch of problems with them, like periodic screen flickers & devices being disconnected. The only way I can fix it is by downgrading to the original BIOS version.

I'm not saying it'll change anything for you because like I said, I agree with the others that you're running out of power from your outlet or PSU. But, hell it's worth a try. I bloody hate these gigabyte boards...

share|improve this answer
Thanks, I'll have to check my bios version. What brand motherboards do you prefer – Jason Oct 24 '11 at 0:30
IMHO, go for Asus & MSI boards. Never had any problems with them. But just in case, I'd do a little bit of digging, just to see if they're are known critical issues that are worth avoiding. (E.g. earlier 1155 boards had faulty SATA2 ports) – Valoric Oct 24 '11 at 1:16
The motherboard manufacturer is not causing this. He doesn't have enough power. – steampowered Oct 24 '11 at 3:57
I know, I said I agree with you. I was just adding that even a faulty BIOS & motherboard can cause problems like screen filters. But, yes obviously a lack of power is the cause. – Valoric Oct 24 '11 at 21:13

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