7990: REALLY BAD FPS- WHY?

Bonblonc · 21 Jun 2014 at 22:25

Just bought a 7990 to replace the 7950, but I'm getting worse benchmarks on it and I just don't understand why.

I ran a benchmark on DiRT Showdown to match the performance a website undertook, using the same parameters and found I only achieved 53 FPS compared to a massive 140 FPS that they got.

Nothing in the system has changed, except the card.
750W power supply.
CPU and GPU temps are normal.
I7 4770k @ 3.9 GHz
latest driver installed
One core is running at 57C and the other 42C

Attepts:
Disabling ULPS
Disabling a BIOS feature that allows GPU power-down
Switching rails
different CCC

Thanks fro any help

FIXED:
moved to new PCI slot and reinstalled drivers.

MissChief · 21 Jun 2014 at 22:27

Are you sure you have Crossfire enabled? The card could be running on a single core.

Bonblonc · 21 Jun 2014 at 22:32

That could be the problem, I can't see an option on Catalyst control center anywhere!

tamzzy · 21 Jun 2014 at 22:54

disable ULPS

Bonblonc · 21 Jun 2014 at 23:20

ULPS disabled did not work although it was a good suggestion.

I'm starting to assume its the psu being too weak

Puppetmaster · 21 Jun 2014 at 23:22

What model is the PSU?

Bonblonc · 21 Jun 2014 at 23:29

******** 750W powerstation

wazza300 · 21 Jun 2014 at 23:32

did you uninstall old drivers with display driver uninstaller? then clean install of ati drivers?

750w should be enough?

borley · 21 Jun 2014 at 23:33

Is it 2 x 8pin power connection or 8 and 6?

Kaapstad · 22 Jun 2014 at 00:13

OP can you run 3dmark11 and post the result link, this will give us an idea as to how well your setup is working.

kaku · 22 Jun 2014 at 00:22

I'm guessing that's a store-brand PSU; they're usually junk.

Try with a decent quality PSU instead.

wazza300 · 22 Jun 2014 at 00:23

kaku said:
I'm guessing that's a store-brand PSU; they're usually junk.

Try with a decent quality PSU instead.

they are actually decent tbh,could be psu but they are ok quality

Puppetmaster · 22 Jun 2014 at 00:30

wazza300 said:
they are actually decent tbh,could be psu but they are ok quality

There is very little information regarding those PSU's. Some believe they are the same OEM as some OCZ's. In my mind, scarce information (lack of reviews etc) suggest to me that its a pile of junk. At any rate, I don't think I would want to be running a 7990 on one.

wazza300 · 22 Jun 2014 at 00:32

Puppetmaster said:
There is very little information regarding those PSU's. Some believe they are the same OEM as some OCZ's. In my mind, scarce information (lack of reviews etc) suggest to me that its a pile of junk. At any rate, I don't think I would want to be running a 7990 on one.

true,but ive used many and one on my current pc for few years,i agree a 7990 might put a huge load on it,but from my experience with them they are decent,only way would be to test with another make/model just to rule it out

Bonblonc · 22 Jun 2014 at 00:38

Thanks for the info.

The psu is old and not the best of quality.

I have a friend with a spare 1500W PSU so im going to try that through my system (long).

Is there a chance the core could be faulty?

wazza300 · 22 Jun 2014 at 00:39

Bonblonc said:
Thanks for the info.

The psu is old and not the best of quality.

I have a friend with a spare 1500W PSU so im going to try that through my system (long).

Is there a chance the core could be faulty?

I doubt it,it simply wouldn't work,probably a power issue,see what the other psu does

usually it crashes aswell if power supply isn't enough but best to test and see

EDIT: id also run other benchmarks just to rule out issue with dirt showdown (you disabled vsync)?

smogsy · 22 Jun 2014 at 07:23

i would ensure the following:
xfire is enabled
Decent power delivery
Run MSI Afterburner to see GPU activity

Marine-RX179 · 22 Jun 2014 at 08:50

Bonblonc said:
Thanks for the info.

The psu is old and not the best of quality.

I have a friend with a spare 1500W PSU so im going to try that through my system (long).

Is there a chance the core could be faulty?

It's not always only about the watts...the brand, model and spec (especially the 12v rail rating), reliability (and checking reviews) on the specific PSU is more important.

JamesM · 22 Jun 2014 at 09:34

You can't disable crossfire on these, something isn't right

Kaapstad · 22 Jun 2014 at 10:46

JamesM said:
You can't disable crossfire on these, something isn't right

You can but you need software to do it.

Choimaloy75 said:
You can disable crossfire with the 7990, but you need to create a profile for the game.

Open CCC, select the 'Gaming' tab then '3D Applications Settings', click on 'Add' then select the .exe that launches your game, click the 'Open' tab at the bottom and that'll add the profile to CCC, now click on the profile and scroll down to the bottom of the screen where the Crossfire options are and you will now have the option to disable crossfire. Click 'Save' and voila, next time you run the game it'll only use 1 GPU. You can double check this when the game is running, you should have a green light on the back of the card lit up next to the 2nd GPU.

EDIT: Also if you want to go back to xfire, just click on the profile again and select 'Default' and make sure frame pacing is on. Or if you've finished with it just delete it.

Hope that helps