Been building systems for years, and I am at my wits end with this one.
I opted to try a crossfire system with two 4890s, and things are not going too well.
Mobo: ASUS P6td Deluxe
Processor: Intel i7-930 @ 2.8
Processor Cooling: Venemous X
Ram: G.Skill F3 1600
Graphics Card: XFX 4890 xfire
Hard Drive 1: Intel SSD
Hard Drive 2: WD 1 TB
Power Supply: Silverstone 1000w
So here is the deal,
Both cards seem to work fine independently, but when I try to do the crossfire thing, I get horizontal lines and a crash with no BOSD.
Crossfire will run, and work for a few minutes then blam~everything locks up, and I have to turn off the comp.
Sometimes, when I reboot, xfire will still be enabled, and other times, it reads only one card, saying the other is disabled in my catalyst graphic properties.
Ive done memtest, checked multiple bios settings, and all my temps are good.
I have used a couple of crossfire bridges, and used them both and then just one at a time.
Both cards seem to be completely stable in the main pcie slot, but I have had problems trying to run just one in the second slot (which Asus says not to do, tried it anyways)
I have contacted ATI, XFX. I haven't heard anything back from XFX, and I have no idea how the ATI guy got his job. (He didn't seem to offer any solution other than "well its either your card, your mobo or your PSU, you should RMA them"- thanks genius.)
All the components of this system seem stable, but I cannot figure this crossfire thing out at all. I had decided to return the card and get a 5870 (which gods I wish I would have done) but they will only offer me a replacement.
I have done about all I am capable of to troubleshoot this rig, and I really can't see myself RMAing all the separate parts.
The only thing I haven't done is flashed the bios on these cards, does that make a difference?
The only other thing of note is directly before or after the crash, both cards fans seem to speed up to 100%. However all readings I have (Aerocool thermal sensor, GPUz, CC temp) says temps are not a prob, is the wonky fans stuff a voltage issue?