Crossfire Questions after Impliment

[krocodile]

Hey there :)
Just had a couple of questions, hopefully simple ones. So, I got my first Crossfire up and running on two X1800 series cards. So far everything seems good, I did a few benchmarks and it didn't crash out so I guess that's a good thing. Anyways, I notice there is a slight wavering on the screen, I'm guessing that might be caused by the crossfire cable? I made sure it was snug and tight, I am running to an analog monitor though using the DVI-Analog adapter. Or, maybe the wavering is lack of power? I wouldn't think power since it's all up and going. However, since I am lacking in power connectors I had to place one card on an already used lead which just has chassis fans on it. Could wavering on the screen be caused by lack of "clean" power? Since this is my first venture into multi GPU territory, any information would be welcome :)

Thanks!

[Dazz]

Could be a lack of 12+ voltage.

[krocodile]

Could be a lack of 12+ voltage.

I guess this is where it become complicated. I am running a PC Power & Cooling PS that should have plenty of power to run this crazy thing. I guess I should have been more specific, though, the wavering is more noticeable when running 3D games, otherwise it's not that obvious. How do I tell which leads are my 12 volt rails? I never was to good at figuring that out.. lol. Most power supplys have at least two right? Oh boy, do I sound like a newbie... I never had to be very concerned about rails till now.

Thanks

[Dazz]

You need to consult the manufature of your PSU as to what the 12+ volt rails are giving you really need at least 40v, alot of PSU's provide 2x 17A 12v railes = 34A 12v.

[krocodile]

510W (650W peak) @ 50°C (industrial rated)
2X more actual power than "500W" home PSUs
Heavy-duty caps, inductors, heat sinks, etc.
Extended sag and surge protection (.99 PFC)
Powerful +12VDC output (34A, 38A peak)
Ultra-tight voltage regulation (+VDC@ 1%)
Super-clean output (+VDC ripple @ 0.5%)

at this model is recommended for SLI.. 38A peak... humm

[Dazz]

There you go it's slightly less amps for what a crossfire rig needs. 38A peak.

[Xion X2]

There you go it's slightly less amps for what a crossfire rig needs. 38A peak.

Don't the 1800's use less power, though? I know that the new 1900 crossfire setups require at least 38A.

Does this "wavering" you see happen only when you're playing games? That would be one way to tell. If you're getting the wavering only when you're playing games then it might be a PSU problem.

[krocodile]

Don't the 1800's use less power, though? I know that the new 1900 crossfire setups require at least 38A.

Does this "wavering" you see happen only when you're playing games? That would be one way to tell. If you're getting the wavering only when you're playing games then it might be a PSU problem.

Yah, the wavering i see appears mostly when i'm playing games when the cards are really pushing. I am thinking, how about if I turn off crossfire, disconnect the Crossfire cable, and then plug my VGA monitor into each card separately without the Crossfire cable in the middle. Then test and see if the wavering is gone? That should then tell me if I have a power issue or interference in my case I would think. Assuming that I can use each card separately and boot into windows and get a display.

I am thinking as a last ditch effort, maybe I go with something like this.
http://www.pcpowercooling.com/products/viewproduct.php?show=S61EPS

Thanks for everyones help!

[krocodile]

An update for anyone who's interested.

I think I found the issue. Someone on another forum suggested that I purchase a new monitor. Well, I didn't exactly do that, but along those lines I just so happen to have a 15" DVI monitor (usually used as a secondary). So, I plugged my 15" DVI into the crossfire dongle and the wavering didn't appear anymore. So, also after reading on a few other forums, people have been experiencing issues with the DVI-analog converter with the same configuration I have as well. Go figure..... It looks like a new monitor is on the horizon for me. I can get some smoking deals on Samsung monitors, so going to look into getting a replacement one with DVI. A move to dual cards is costing me more than I bargained for. :thumbdwn:

[Xion X2]

A move to dual cards is costing me more than I bargained for.

Heh, welcome to the world of PC enthusiasts. I set out to spend no more than $1,000 on my last build and ended upwards of 1,800$ :)

[Dazz]

Hmm that was some what expected i guess it must be to do with the refresh rate what about CRT's do they work ok with them?

[krocodile]

From what I read, CRT's are just as issue prone. It appears to be related to the DVI-Analog converter and the crossfire cable. Soooooo, to make a long story short. I worked about 50 - 60 hours this week at my job, and my boss being the nice guy he is, is going to buy me a brand new monitor with DVI as a bonus! Whoopee!! So, I got a new one on the way next week which should take care of this annoying wavering issue once and for all. Now, if only I could calm those bad boy video cards down when they get warm.. lol.. it sounds like an airplane if both cards crank up the fans! I'll give an update when I get my new monitor.

[krocodile]

Ooops, I have been meaning to update this thread. I got my new monitor a few days ago... and everything looks great! I opted for a 19" Viewsonic 2ms LCD w/ DVI. Thanks a lot for everybody's input! Now, back to playing without getting a headache.

[SH64]

Q : Since you are a XF owner .. i'd like to ask you if you get any kind of mouse lag when playing XF enabled games ??
i mean a feel of a mouse lag when framerate goes below 40-35fps or something close ..
i'd like to hear your experiance in comparsion to a single GPU setup , framerate/mouse-wise

if you cant make a direct comparsion to another single-GPU setup , then its no use for me & if you are not certain about this issue just tell me you are not certain.

[Dazz]

Well he says that the issue has been resloved so that good, was thinking that wasn't there an issue with crossfire and monitor due to the encoders on the chips.