I recently added another ATI 5870 card to my system to experiment with ATI Crossfire (dual GPU) performance increases.
However, I've had a lot of intermittent stability problems, most seriously a set of oscillating horizontal bands which appear during gameplay and become quite severe, to the point that you can barely see the screen to exit the game!
It looks a little like this:
My system has an overclocked Sandy Bridge CPU that has been rock stable with a single 5870, but adding the second video card and enabling CrossFire seems to be problematic. The cards are both installed fine, fully seated with plenty of space between them, have both PCI 6-pin power connectors connected, and my 850 W power supply should be ample.
The Catalyst hardware properties look fine:
Primary Adapter
Graphics Card Manufacturer Powered by AMD
Graphics Chipset ATI Radeon HD 5800 Series
Device ID 6898
Vendor 1002
Subsystem ID 2289
Subsystem Vendor ID 1787
Graphics Bus Capability PCI Express 2.0
Maximum Bus Setting PCI Express 2.0 x8
BIOS Version 012.018.000.001
BIOS Part Number 113-C00801-XXX
BIOS Date 2010/02/08
Memory Size 1024 MB
Memory Type GDDR5
Core Clock in MHz 875 MHz
Memory Clock in MHz 1225 MHz
Total Memory Bandwidth in GByte/s 156.8 GByte/s
Linked Adapter
Graphics Card Manufacturer Powered by AMD
Graphics Chipset ATI Radeon HD 5800 Series
Device ID 6898
Vendor 1002
Subsystem ID 2289
Subsystem Vendor ID 1787
Graphics Bus Capability PCI Express 2.0
Maximum Bus Setting PCI Express 2.0 x8
BIOS Version 012.020.000.001
BIOS Part Number 113-C00801-100
BIOS Date 2010/03/31
Memory Size 1024 MB
Memory Type GDDR5
Core Clock in MHz 850 MHz
Memory Clock in MHz 1200 MHz
Total Memory Bandwidth in GByte/s 153.6 GByte/s
I've tried the following:
-
swapping the primary (ever so slightly faster at 850 MHz vs 875 MHz) and secondary cards, so now the primary is the slower not faster one.
-
installing the latest beta ATI Catalyst drivers
-
installing the latest CrossFire application profiles
All to no avail!
Best Answer
This was a tough one.
After many hours of trial and error, someone mentioned to me that overclocking could be the issue:
I thought overclocking couldn't possibly be it, since this system has been ultra stable for MONTHS with the current settings.
But setting BCLK to 100 (default) from the "auto extreme overclocker" override of 103 and not overclocking does seem to have worked. I was able to play several BF2:BC rounds with no issues, though I did see a hint of the horizontal banding at one point, it went away by itself.
So, watch out for any PCI Express overclocks when running an ATI CrossFire video card setup!
edit: additionally, I was seeing some other .. oddities .. that were resolved by setting the two video cards to the exact same clock and memory timings in the Catalyst Control Center AMD Overdrive section (although they are both 5780 cards, obviously, they came from the manufacturer with slightly different clock and memory timings). Thus, I also strongly recommend making sure both cards in Crossfire have the same settings.