High DX11 CPU overhead, very low performance.

The 290 never cost 550$ and it launched a full year before the 980. -.-

 

Yes but now that I'm considering getting the 980 it would have been better had I waited.

 

With that logic you wait forever. The 290 is a fine GPU actually, and it will probably serve you really well in the DX12 era too. I would change it only for a card that went below 28nm if I were you (as I plan to do with my 7970).

Unfortunately it seems that my motherboard's second PCI-Ex16 slot is electrically x8. I get x8 even with the two cards unplugged and only the gpu on the last "big" slot.
It is a non-issue really, but it was nice to check.

 

Problem is I would have liked to go Crossfire with the 290 but had to return the second card because of heat. I also don't feel confident enough in my computer building ability to go liquid.

 

Oh ok... Yeah like I said I was having the same issue and I only realised it because I was looking at old Aida benchmarks and was wondering why memory read/write (for the GPU) were higher... Which made me realise the GPU was running at 8x... Turned out for me it was due to the network card and sound card being plugged into PCI Express 8x slots (which made everything 8x). Moving them to the mini PCI Express slots and moving the GPU to PCI Express Slot 3 fixed the issue for me (can't really call it an issue). But yeah almost double the vRAM read/write speeds. Which surprisingly doesn't affect benchmarks by much (other than the Aida GPU Benchmark).

 

Maybe you've already checked this but have you made sure your PCI express setting in the bios is set to gen3?

 

With enough airflow in your case heat is not a problem. So check your airflow.

There are some nice findings in this thread, keep up the good work

 

Maybe that pci-e 2.0 is not good after all. I'm running pci-e 3.0 8x/8x with a sound card in the very top slot. If I could only reduce the PCI-e to 2.0 I could do further testing to see if that affects the test.

 

I have tons of airflow in my case. I couldn't have more airflow in my case. Heat is still a problem.

 

Going to give them a look, my 7950's are also from Sapphire. I've run the test also at PCI-E 2.0@8x, as I had only disabled crossfire, didn't remove the 2nd card.

 

Sounds like you have a problem with your case airflow, honestly. That's one of the reasons I love vertical cases, although there hasn't been a proper one out since the Raven RV03.

My motherboard has a P67 chipset and I have a Sandy Bridge CPU, so no PCI-E 3.0 for me

These speeds refer to the access that the GPU has to the system ram I believe. So they only truly matter if you're out of VRAM.

There might be a different setting with your motherboard/gpu memory timings. It's a non issue really, it just made me curious. What is the 3dMark score you get with the 1023.3 drivers with a single GPU?

 

Yep, sometimes CFX is simply impossible in some cases due to temps even with optimal case airflow.

It was imposible for me to use CFX untill i put a serious WC loop in my PC.

The first GPU reached 90 Cº 30 seconds in a game menus...not even in the game itself!

Now i play games with a moderate-high GPU OC and always under 50 Cº but this cost MONEY.

A good WC loop is an important investment to only use it with a pair of GPUs blocks and a CPU blocks, normally a bigger, powerfull and more expensive GPU is mopre convenient than CFX.

 

I see you have the HAF912, that's a decent enough case for proper airflow indeed. What CPU cooler do you have, as you are overclocking your cpu quite a bit.

@sammarbella, water cooling is always better than air but it adds up to the total cost. So then it could be word it to put that money in cooler GPU's. However, it does look good and you have a lot less noise.

Water cooling does not generate heat inside the case as air cpu cooling does. So when airflow is not optimal heat tends to build up inside the pc case. Aftermarket gpu cooling does the same, but is often a lot quieter then reference gpu cooling.

 

What about space between GPUs?

Look at the space bettween my 290X lightnings (3 slots GPUs) BEFORE the WC loop:



No matter how much airflow you put there even without side door ...it doesn't work!

When i put WC loop it looked like this:



It worked fine.

 

you can always do this. Strap a aio liquid cooler to your graphics card and use the fan of the stock intel cooler to cool it down. Just google "amd the red mod" and you will find how to do it. Will bring your temps down a lot. You don't even need a big cooler. Something like h55-h60 will work just fine.

I did it for a while but had to return the cooler cause it was making a buzz noise so I installed the stock cooler. I realize that my cooler was just fine at 75C-80C on top card. Oh sorry for it looking bad but I'm not trying to make it look nice I was just testing how it would work and was going to do the other card when I heard the buzz noise.

Anyway I saw temps at about 50C on gpu max when playing bf4 shooting into the ground with lmg having vsync off, unlimited fps and ultra preset so was taxing both gpu's 100%. was running core 1150 memory 1500. VRM never went above 60%.


Also don't judge the 2 crossfire bridges. I run korean panel and have to use 2x crossfire bridges for it to work

 

That's why you get vertical cases gentlemen

Spoiler

 

My system has one slot between them and the top card goes to 90 C, but that is acceptable for the 290.

 

You have a reference design cooler?

 

You should SERIOUSLY consider the use of spoilers for BIG images!

Edit: Thanks for the edition!

 

Hey, didn't know these existed. Look a lot more effective in the airflow department.