SLI problem please help

[Glaith]

G'day all,

 

Ok so I have just been luck enough to get a hold of 2 x 980's for very cheap.

 

I am running a Cooler master 700watt psu. ( It ran 2 x 290s with no problems)

 

My problem is when running SLI with normal clocks on CPU and over clocks on CPU and playing with voltages I get the same result. System instant shuts down (turns off) and reboots.

So I'm like OK its gotta be a power issue. So I Jury rig up my 2nd PSU to run the 2nd card and still have the same problem except the system does not shutdown it just black screens and locks up.

 

I have tested both cards and stress tested them individually and they are fine and work with system overclock.

I have also tested the 2nd pci e slot and all works fine no shut downs.

 

So before I go out and buy a new PSU I wanted to hear all your input.

And go

 

 

[stealth80]

Have you tried the new PSU exclusively to rule out the current one? Also did you do a full DDU driver remove from your 290's?

 

Does the black screen occur on boot or when windows loads?

[Glaith]

I have done the DDU,

 

And don't have a new PSU to test, I may have to borrow one if i cant find some one who has 800+ or more.

No the shutdown / blackscreen will only occur if i have the card under load like in heaven or valley.

 

[RUWO_builder]

2 minutes ago, Glathier said:

I have done the DDU,

 

And don't have a new PSU to test, I may have to borrow one if i cant find some one who has 800+ or more.

No the shutdown / blackscreen will only occur if i have the card under load like in heaven or valley.

 

Than pretty sure its a power issue. Try watching the power ussage in heaven.

if it Raises just before a crasch, theres your anwser.

[Glaith]

I can just use msi afterburner to see the power usage?

[RUWO_builder]

4 minutes ago, Glathier said:

I can just use msi afterburner to see the power usage?

Also true, i forgot About that

[Glaith]

So it must be the problem, I ran the test with just one card and its peaking at 65%

not much head room for the 2nd card. Im going to run the test with 2 cards and see what it hits.

[Glaith]

Ok with the 2 card they both peaked at 62% does this mean its going to 120%?  and is using to much power?

 

[RUWO_builder]

That percentage is howmuch under the Cards power limit it stays. Not of the psu limit. This doesnt tell you anything. You need to look for sudden changes. For chraches

[RUWO_builder]

The cards power limit is when it starts to lower clocks in order to. Not use to much power

[MCCOPRA]

Welcome to NVIDIA SLI HELL - Had the same issue and gave up with SLI getting a single 1080ti and be done with it and never ever do sli again.

 

here is my previous topic about same issue

The problem is with current gen drivers messing up SLI setups nothing to do except prey for a good stable driver but its getting worse and worse every release now.

 

[Glaith]

So drivers are able to cause a complete system shutdown? .

 

Understandable if it locks up but no it seems when the cards get underload it just drops power and resets.