I installed a new video card the other day, ATI Radeon HIS x1550 (low profile), into my HP Pavillion Slimline s3100n. The good news is my games aren't crashing anymore since the upgrade, the bad news is now I have this real light fuzz, slightly resembling rippling water on my screen. Here's my system specs if needed. Any help or a point in the right direction would be awesome. ^^
=============================== System =================================

CPU = Unknown AuthenticAMD Processor
CPU Speed = 2108 MHz
No. of CPUs = 2
OS = Microsoft Windows Vista Ver 6.00.6000
Version of DirectX = DirectX10.0
Main Memory = Capacity:1021MB : Free Space:448MB
Graphics Card = ATI Radeon X1550 Series
Type of Chip = UnKnown Video Chip
Video Driver = atiumdag.dll
Version = 7.14.10.555
Updated = Thursday, December 20, 2007 8:48 PM
VendorId = 0x1002
DeviceId = 0x7143
SubSysId = 0x204E17AF
Revision = 0
VRAM =
AvailableVidMem = 127.6MB
AvailableTextureMem = 382.0MB
Motherboard = Hematite-XL
Manufacturer = ASUSTek Computer INC.
Version = 1.00

Is your monitor connected using VGA or DVI? If you're using VGA output, it may be interference thats altering the picture.

Actually, yes. Which brings up another problem I am having. My DVI connection isn't working. It shows the booting screens at first, but once it passes the Vista loading screen and goes to load the desktop the screen goes black...
I couldn't find any settings within Catalyst to switch my default connection to DVI, nor in the control panel. Anyone got any ideas? =) tyvm

Your DVI port is working, Windows Vista just needs to be instructed to utilize it.

* Right click your desktop, click Personalize.
* Click Display Settings.
* You should see a dropdown with your video card. Change it to the "Secondary" option.
* Adjust the resolution slider to match previous settings. (If using an LCD monitor, use the screen's maximum resolution for best results)
* Make sure the "This is my main monitor" box is selected. Then click OK.
Switch your monitor to DVI input, and you should see the picture. Do so quickly, as Windows reverts back to previous settings if you don't confirm being able to view within 15 seconds.

Hope this was helpful!

I went to display settings and set it to the second one in the drop down bar, both my vga and dvi are connected btw, set it to main and hit apply. Then I hit the button on the monitor that tells it to go to DVI and it just showed a black screen for a second, then switched to desktop. I unplugged VGA cord and my monitor turned off. I'm confused. I went in further and checked for monitor driver updates, and when I got the card, just a few days ago, I updated driver immediately. So it's all up to date as far as I know. Oh, and yes, I use a LCD monitor, it's some off brand i've never heard of (SVA) but it didn't do this prior to installing the video card. Thanks for your assistance so far, btw, Jwooden =)

When you hit apply and switched to DVI, you should have seen a window appear asking you to confirm your change. (Meanwhile, VGA input should go black) If you see the message, click Yes to indicate that you want to keep the new settings. Then, you may disconnect VGA.

If you never saw this window, then the 15-second wait expired and Windows reverted back to VGA. Check to make sure that the resolution slider is set properly. Use the monitor's max/native resolution, indicated on the box or manual, not necessarily the slider's maximum.