Swapped SLI cards places, strange problem.

[Mkilbride]

So, my first GPU had temp problems, 15-20c higher than the second. This was mainly because my second GPU, blocked it's airflow pretty badly.

I decided to swap the cards places for the hell of it. Seeing as the second GPU seemed cooler in general. That solved my temp issues, oddly enough, the first GPU, now with enough air flow, seems to being alot better. No dust or anything either, I should change the thermal paste, but anyways, for now, it works.

Weird issue is...Desktop is fine, videos are fine, ect, nothing appears to wrong.

Except: in-game SLI, my second GPU, previously my first GPU, is now used about 20% LESS than my first GPU, where in the past, both GPU's were used equally. I tried disabling and re-enabling SLI to no avail.

Also, I get a strange color flashing thing, that looks like it's switching constantly between 16bit & 32bit. It's quite odd. Disabling SLi seems to fix this issue...which means, well, I don't know it means, something wrong with the second GPU, that was previously my first GPU?

 

[alienware]

Load up GPUZ and see what the lanes are running at. By switching them around it's possible the bios changed something.

A pic would also help.

 

[NRG!]

reinstall drivers

 

[Mkilbride]

Huh. That's the oddest thing. The second GPU, which is now the first GPU, is running @ @ PCI-E 2.0 x4, though GPU-Z reports it as a PCI-E 2.0 x16 slot. Curious, as the slot previously ran @ 8x in SLI. My second GPU, previously the first GPU, is running @ PCI-E 2.0 16 @ x8

I didn't think swapping the cards around would change so much.

 

[alienware]

Ah as I suspected your board got freaked out. It's happened to me before dude

 

[Mkilbride]

Ok...and...that's good to know it happened to you...but solution?

 

[alienware]

Just went to bios and loaded optimised defaults, then redone all my settings.

Have you inspected the bioses on the cards? I would. Make sure you don't have a mismatch.

 

[Mkilbride]

Just went to bios and loaded optimised defaults, then redone all my settings.

Have you inspected the bioses on the cards? I would. Make sure you don't have a mismatch.

So I lose my OC settings for my CPU & RAM? I have to redo all that...?

And, one of my cards Bios is infact different, months ago I flashed it based of a topic on OCN which allowed the voltage to go higher, and indeed it did seem to OC better. Never did it to second card, but didn't think it was much of an issue.

Second GPu tops out around 1176 Boosted, with no OC, first GPU is around 1293mhz boosted.

 

[Mkilbride]

Sorry to bump.; but I loaded optimized defaults. Didn't do anything.

Gonna try re-seating the card, some people said it can sometimes be almost out of the slot and not be running fully, which is odd.

- They're both 2.0 x8 now, which is right for my mobo.

However, the screen color flashing still happens. It does not happen when SLI is disabled, which is what confuses me...makes the second GPU look to be the issue, but nothing I could find was wrong wtih it...hmm.

Found a few users with likewise problems:

http://www.overclock.net/t/802240/solution-for-flickering-screen-with-nvidia-sli

http://forums.guru3d.com/showthread.php?t=326664

Might be the SLI bridge...why it went suddenly ? I don't know.

https://forums.geforce.com/default/topic/451575/sli/fixing-sli-screen-flickers/

I guess I can try re-seating BOTH cards...and a new SLI bridge.

http://www.amazon.com/Asus-Nvidia-f...TF8&qid=1364779503&sr=8-1&keywords=SLI+bridge

This is the one I have now, needed it because of the way my GPU's are, the flexibility. Got it in August...

Anyone else got suggestions for SLI cables that can flex and are at least as long?

 

[alienware]

A bad SLI bridge usually results in flickering like a strobe light. Try cleaning the edge connectors with some sort of alcohol. They tend to get flux on them when they are sprayed during manufacturing and they can be dirty.

I've read about those bioses that allow higher voltage but stayed away from them because Nvidia blocked voltage tweaking on 104 for a reason, and that reason is they were already screaming their entrails out of their arse before release.

There was a guy who was doing the Nvidia EU Facebook updates and he posted one day to say something like "OMG 50% bios !".

What he meant was that the cards were initially clocked around 700mhz and Nvidia slapped on a bios that took them right to their limit. That's when Nvidia released a statement to say that Tahiti was underwhelming because they never EVER expected what was going to be the 660ti to compete with Tahiti.

It did, and that'w why Titan is now Titan and not a 680 and the 680 was the 670ti ETC.

That came at a cost though, and that meant that upping the volts would likely blow the core sky high.

I would make sure both cards are running the same bios because in SLI everything mirrors so clocks will be the same ETC.

 

[Mkilbride]

Well, I re-adjusted the second card and blew on the connectors, swapped them, issue still exists in SLI...

Thinking about buying another Bridge...any suggestions, based on what I've told you above?

I tried moving the Bridge around while in-game, and while I DID get it to stop flickering...colors looked like they were 16bit.

 

[alienware]

Did you make sure the bioses match?

A bridge can be found easily and cheaply on Ebay tbh. I bought one before I emailed MSI.

 

[Mkilbride]

Yes, I realize that...but I'm asking for suggestions, as I need a 120MM one that can flex. The one I posted before is what I have now and it's less than a year old.

 

[Mkilbride]

Got another one. Seems to be working now, color issue is gone...

I compared it to the old cable and if you put em next to each other, you could never tell the difference...so quite odd.

 

[alienware]

Glad to hear it. I've had several bad SLI bridges over the years and they were all aesthetically fine.