amd xfx hd 7950 dd crossfire temperature problems

VJG1588

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Mar 29, 2013
8
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10,510
NEED HELP
I HAVE 2 7950 XFX DD
ONE WITH CORE 800MHZ
AND THE OTHER WITH 900MHZ
ITS WORK FINE THE FRIST ONE MORE COOL THAN THE OTHER BUT
WHEN I PUT IT IN CROSSFIRE I HAVE A BIG PROBLEM
FIRST:
THE 900MHZ IN THE FIRST PCI-E
THEY WORK FINE BUT THE 900MHZ GET
99 DEGREES
AND THE 800MHZ ONLY 64 DEGREES
NOW IF I PUT THE 800MHZ ON THE FIRST PCI
I GET THIS PROBLEM
IT WORK FINE
BUT WHEN THEY GET 73 DEGREES
THE GAMES GET 10 FPS AND GET BACK TO NORMAL THAT IT repeated every 4 or 5 minutes
SO PLEASE NEED HELP
SORRY MY BAD ENGLISH
MY SYSTEM:
CPU: AMD 8350
PSU: 1000W ASUS
MB: gigabyte ga-990fxa-ud3
RAM: (2X4) 8gb corsair vengeance
NOTE: I PUT THE CARDS ON THE PCIX16 PORTS
 

Rammy

Honorable
Hard to tell from your wall of caps, but it seems like the top card is consistently overheating, whichever card you put in the top PCIe slot?

If this is the case, it is likely that the 2nd card is entirely blocking the airflow to the top card. Given your motherboard has 4 PCIe x16 slots, have you tried keeping the cards further apart?
 

VJG1588

Honorable
Mar 29, 2013
8
0
10,510
in my knowledge my motherboard has only 2 pci x16 the others are 4x
but why when i put the 900mhz card on the first pci express
it get 99 degree?
and
when i switch it they get the same temperature, but fail the fps in game.
so is the position?
thanks
 

Rammy

Honorable
From the motherboard support page
2 x PCI Express x16 slots, running at x16 (PCIEX16_1, PCIEX16_2) (Note 3)
2 x PCI Express x16 slots, running at x4 (PCIEX4_1, PCIEX4_2)
2 x PCI Express x1 slots
(All PCI Express slots conform to the PCI Express 2.0 standard.)
1 x PCI slot

From a glance at the pictures, it seems like if you have it connected correctly, there should be a space between graphics cards, like this - http://rog.asus.com/wp-content/uploads/2013/01/Crossfire-goldinger.jpg
Some motherboards force you to stack cards next to each other, like this -
http://www.blogcdn.com/www.engadget.com/media/2009/08/nvidia-sli-08-10-09.jpg

If you have a slot gap (you should be able to see the slot labelled PCIEX4_1 between the cards if you look down) and you are still getting overheating in the top card then it suggests that you might have airflow issues in the case.

Also, if I understand correctly you have two HD7950s, one is an XFX AMD Radeon HD 7950 Double D Black Edition 3GB (900Mhz) and one is a XFX HD7950 Double D 3GB (800Mhz). As I understand it, they should just match each other on speed, I think the 2nd card follows the first so if you have the fast card in PCIEX16_1 it should make the 2nd run at 900Mhz though it's definitely worth checking this with software as it's not something I have much experience of. In general it's a good idea to buy 100% identical cards to dodge any potential issues, but I think this should work fine.

It's clear that your temps are way too high. I'd be curious to see what kind of temps you are getting just with a single card.
 

VJG1588

Honorable
Mar 29, 2013
8
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10,510
ok the card works great alone
in crysis 3 :
900mhz (is not black edition is fx 795a tdf VL0 i cant find it in the xfx web) 72 degrees
800mhz (FX 795A TDFC ) 68 degrees
so the problem is when i put it in croos fire the master has 800mhz clock and the other 900mhz
so when the second has 80 degrees i get lag
so if i can get the new bios for the 800mhz in order to get the 900mhz may be fix the problem
thanks again for you help
NOTE:(i dont know how to put images on the answer :( )
:( i cant find the bios for the 800mhz card the xfx web is under construction
 

crunchybobjones

Distinguished
Mar 25, 2011
4
0
18,510
sounds like u have a heat problem.. is the cpu air cooled ? i had a problem with case temps till i water cooled the cpu.. it takes a lot of heat out of the case, i ran crossfire with 2 hd 6950's , just upgraded to the hd 7950 ordered the second card it will be here Wednesday but never had a heat problem since i installed h60 water cooler on cpu .. it pulled a lot of heat out of the case and i have the same motherboard