SLi performance terrible in BF3

holymonk · 4 Nov 2011 at 00:02

I am running x2 GTX 460 in SLi but I am only getting 20 fps on high settings.

When I switch to a single card only I am getting 40-60 FPS.

Anyone know why this might be?

stulid · 4 Nov 2011 at 00:14

Do you have the latest drivers installed?

Is the bad performance in SLI only with this game? all other games give you the performance you would expect from two cards?

holymonk · 4 Nov 2011 at 18:00

Well, I do have the latest drivers, the FPS is fine on 1 single card, but terribad with Sli, in certain games I am seeing a good FPS increase (Arma II) others (HoN) its a bit stuttery?

stulid · 4 Nov 2011 at 18:04

Just noticed your PSU, they do have a reputation following them, Search for "hiper explosive club"

Also a weak under power PSU can cause,

bad 3D performance
crashing games
spontaneous reset or imminent shutdown of the PC
freezing during gameplay
PSU overload can cause it to break down

Buchanan0204 · 4 Nov 2011 at 18:27

GTX 460 with a Hiper PSU

holymonk · 4 Nov 2011 at 20:33

I get the Hiper explode somtimes, but would that lead to bad Sli performance?

stulid · 4 Nov 2011 at 21:06

holymonk said:
I get the Hiper explode somtimes, but would that lead to bad Sli performance?

The 5 effects I mentioned above are from Guru3D reviews when they test video cards power consumption, one of the effects is poor performance and BF3 does look like the sort of game to stress a system both CPU+GFX.

holymonk · 5 Nov 2011 at 23:35

What sort of FPS would you expect to get from 3dMark11 extreme mode, in SLi i am getting 10, single card 5?

GTO656 · 6 Nov 2011 at 01:19

Yes dude you should change the PSU to Corsair/Antec wud be great.

moody89 · 6 Nov 2011 at 09:01

First of all, just to eliminate the possibility, how are your temps looking while you're playing the game?

Here are the power consumption figures for a GTX460 from a Guru3D review (the site that stulid mentioned).

http://www.guru3d.com/article/geforce-gtx-460-review/13

As you can see, on that site they recommend a 650-700W, so you're just below borderline here. Obviously this isn't hard set but take it as a guideline at least. I'm not going to immediately blame your PSU and say to buy a new one, particularly since your unit actually got a pretty favourable review on JonnyGuru:

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=102

However, performance issues in SLi are most often caused by driver, heat or power issues. It may be worth completely uninstalling your drivers fr your card and then installing the current drivers from fresh. If possible, I would swap out your PSU for a different (more powerful) unit to see if this makes any difference. It wouldn't want to assume your PSU outright but at this point in time, it has to be seen as a possible cause at least so if you can swap it out, you can eliminate or confirm that possibility. Work your way through this and the replies above and post back with more info. Good luck!