Crossfire GPU's only getting 40-60% Usage on certain games?

LtMatt · 7 Sep 2013 at 19:44

There you go the proof is in the pudding. Your score looks fine and about right.

The probable reason for my slightly higher score is my higher cpu clock speed, memory speed, coupled with very tight first and secondary timings on my memory.

Marine-RX179 · 7 Sep 2013 at 19:47

xTommy92 said:
Did not want to buy a new Motherboard just for a new GPU so wanted to try it with this, honestly thought that x4 (PCI_E 2.0 x8) would be fine, just a little less performance.
Surely the Motherboard is not causing this problem?

LtMatt said:
You're on pci-e 3.0 and it should be fine i would have thought as its faster than pci-e 2.0. The scores look about right to me.

http://www.xbitlabs.com/articles/mainboards/display/gigabyte-ga-z77-d3h_2.html#sect0
"The Gigabyte GA-Z77-D3H doesn’t use the ability of the Intel Z77 Express to share CPU-integrated PCIe lanes between graphics slots and only offers one PCIe 3.0/2.0 x16 slot for a discrete graphics card (it always works in full-speed x16 mode). NVIDIA SLI is not supported but you can build a multi-GPU configuration by using AMD CrossFireX and the second PCIe 2.0 x16 slot (which only works in x4 mode and disables the PCIe 2.0 x1 slots). There are also two PCI slots for expansion cards."

xTommy92 · 7 Sep 2013 at 19:48

Good to know, thankyou!
Had a little go on Tomb Raider, I am getting 99% usage on both cards until I hit areas of intense fighting and the usage on both cards drop to 50-60%. It should be the other way round. 99% @ 150-180fps to 50-60% @ 75-90fps?

Tom

LtMatt · 7 Sep 2013 at 19:50

Marine-RX179 said:
http://www.xbitlabs.com/articles/mainboards/display/gigabyte-ga-z77-d3h_2.html#sect0
"The Gigabyte GA-Z77-D3H doesn’t use the ability of the Intel Z77 Express to share CPU-integrated PCIe lanes between graphics slots and only offers one PCIe 3.0/2.0 x16 slot for a discrete graphics card (it always works in full-speed x16 mode). NVIDIA SLI is not supported but you can build a multi-GPU configuration by using AMD CrossFireX and the second PCIe 2.0 x16 slot (which only works in x4 mode and disables the PCIe 2.0 x1 slots). There are also two PCI slots for expansion cards."

Excuses me for being retarded marine but are you saying the first slot is pci-e 3.0 x16 and the second slot is pci-e 2.0 x4?

If so id say thats a problem that tommy needs to rectify at some point. When i used pci-e 2.0 x16 x4 the x4 gpu usage rarely went above 90%.

Marine-RX179 · 7 Sep 2013 at 19:51

xTommy92 said:
Good to know, thankyou!
Had a little go on Tomb Raider, I am getting 99% usage on both cards until I hit areas of intense fighting and the usage on both cards drop to 50-60%. It should be the other way round. 99% @ 150-180fps to 50-60% @ 75-90fps

The scenes which the frame rate drop to 75-90fps and with GPU usage dropping probably just mean that's the frame rate your CPU capable of pushing at those scenes.

LtMatt · 7 Sep 2013 at 19:53

Marine-RX179 said:
The scenes which the frame rate drop to 75-90fps and with GPU usage dropping probably just mean that's the frame rate your CPU capable of pushing at those scenes.

I'd agree with you normally Marine but this is Tomb Raider. Its very un-demanding on the cpu generally, or so i thought.

Marine-RX179 · 7 Sep 2013 at 19:54

LtMatt said:
Excuses me for being retarded marine but are you saying the first slot is pci-e 3.0 x16 and the second slot is pci-e 2.0 x4?

No not at all. I'm not 100% certain on the matter either...but from the article, it does seem to be point to that the 2nd PCI-E x16 slot is indeed only x4 at PCI-E 2.0 when using crossfire.

LtMatt · 7 Sep 2013 at 19:58

Marine-RX179 said:
No not at all. I'm not 100% certain on the matter either...but from the article, it does seem to be point to that the 2nd PCI-E x16 slot is indeed only x4 at PCI-E 2.0 when using crossfire.

I'd say thats a problem then and could definitely account for low gpu usage on one of his gpu's. If i found that at x16 x4 pci-e 2.0 id say it would be just as noticeable, probably more so at pci-e 3.0 x16 pci-e 2.0 x4.

That said, its not a huge issue. You'll still get mighty gains. Its just you'll lose maybe 5% or more performance and the slower lane gpu might slack a bit in usage from time to time.

Marine-RX179 · 7 Sep 2013 at 19:58

LtMatt said:
I'd agree with you normally Marine but this is Tomb Raider. Its very un-demanding on the cpu generally, or so i thought.

But you have to bear in mind that it is not pushing for 60 (fps). I mean I am using a 120Hz monitor, and I can tell you that while games in general are GPU limited, overclocked i5 is usually not capable at keeping frame rate at constant 100fps+, particularly when a game's semi-CPU-demanding not perfectly coded to use 4 cores fully.

If you look at games CPU scaling benchmarks in general, you'd hardly see overclocked i5/i7 having having minimum frame rate of 100fps+ for modern games (even when not under GPU limited situation).

LtMatt · 7 Sep 2013 at 19:59

Marine-RX179 said:
But you have to bear in mind that it is not pushing for 60 (fps). I mean I am using a 120Hz monitor, and I can tell you that while games in general are GPU limited, overclocked i5 is usually not capable at keeping frame rate at constant 100fps+, particularly when a game's not perfectly coded to use 4 cores fully.

Fair enough. I'm just not sure, this is a tricky one. I forgot he was at 120hz.

xTommy92 · 7 Sep 2013 at 20:51

Haha, getting even more complicated now!
Sorry for going on but paying for an extra GPU, I am wanting to get the performance out of it. Even if that means a new Mobo and/or i7 so be it but for the moment I am just wanting to see how it can perform maximally on a i5 and Z77-D3H.

Tom

Marine-RX179 · 7 Sep 2013 at 21:05

xTommy92 said:
Haha, getting even more complicated now!
Sorry for going on but paying for an extra GPU, I am wanting to get the performance out of it. Even if that means a new Mobo and/or i7 so be it but for the moment I am just wanting to see how it can perform maximally on a i5 and Z77-D3H.

The thing is...unless the game would use more up to 5-6 threads, the i7 will not offer any better performance than the i5. The problem you are having now is more to do with CPU bottleneck I would imagine.

I hate to say this, but Intel's small incremental performance increase for this last few gens has really ruin it for us who have moved onto 120/144Hz monitor for gaming.

xTommy92 · 7 Sep 2013 at 21:07

http://i497.photobucket.com/albums/rr339/oO13LACKARTOo/SpikingGPU.png

Sorry not quite sure how to bring the image up but is this right?
This is GPU1 idle, obviously the usage is low but could this be anything related to the low usage?

Tom

xTommy92 · 7 Sep 2013 at 21:09

Marine-RX179 said:
The thing is...unless the game would use more up to 5-6 threads, the i7 will not offer any better performance than the i5. The problem you are having now is more to do with CPU bottleneck I would imagine.

I hate to say this, but Intel's small incremental performance increase for this last few gens has really ruin it for us who have moved onto 120/144Hz monitor for gaming.

What about trying to overclock a little more, maybe 4.8-5.0Ghz?

Tom

Marine-RX179 · 7 Sep 2013 at 21:12

xTommy92 said:
What about trying to overclock a little more, maybe 4.8-5.0Ghz?

If you can overclock it higher, it will certainly help. However it won't make a day and night difference, but more like possibly a couple fps higher (which is not bad to be honest).

However for IvyBridge i5 overclocking to 4.70GHz the temp would most likely already start to get out of control even if you got good CPU cooler. You might need to considering delidding the CPU and get rid of the sealant, but it's not something I would recommend to anyone who don't have complete confidence with their hands:
http://www.youtube.com/watch?v=XXs0I5kuoX4

xTommy92 · 7 Sep 2013 at 21:22

Marine-RX179 said:
If you can overclock it higher, it will certainly help. However it won't make a day and night difference, but more like possibly a couple fps higher (which is not bad to be honest).

However for IvyBridge i5 overclocking to 4.70GHz the temp would most likely already start to get out of control even if you got good CPU cooler. You might need to considering delidding the CPU and get rid of the sealant, but it's not something I would recommend to anyone who don't have complete confidence with their hands:
http://www.youtube.com/watch?v=XXs0I5kuoX4

I.e me! xD
I watched that video the other after you posted, do you not find the performance good enough with a 120Hz on your setup?

Tom

xTommy92 · 7 Sep 2013 at 21:25

Also downloading Crysis 3 at the moment, going to see how much that tortures my system when it's done!

Tom

Marine-RX179 · 7 Sep 2013 at 21:36

xTommy92 said:
I watched that video the other after you posted, do you not find the performance good enough with a 120Hz on your setup?

The thing is...Intel's closest competitor AMD...they haven't even been close to offering enough threat to put pressure on Intel to force them into bring out much more powerful stuffs at reasonable price level. I think most of us would agree Intel need a smack in the face by AMD like what AMD's Athlon 64 did to Pentium 4 back in the days, and forces Intel to kick into high gear.

There's simply no CPU at the moment can hold minimum frame rate 100fps+ for majority of modern games at the moment, except overclocked SandyBridge-E 6 cores on games that would use 6 cores fully.

xTommy92 · 7 Sep 2013 at 21:42

So is CPU bottleneck where the CPU does not have enough power or clock speed to run both GPU's?
Surely though for a few frames more it is not worth overclocking the CPU unless I will definitely notice more smoothness.

Tom

Marine-RX179 · 7 Sep 2013 at 22:39

xTommy92 said:
So is CPU bottleneck where the CPU does not have enough power or clock speed to run both GPU's?
Surely though for a few frames more it is not worth overclocking the CPU unless I will definitely notice more smoothness.

It's usually referred as "CPU scaling".

To put simply, with the few exception such graphic demanding games like Crysis 3, crossfire 7970 should be able to do minimum frame rate above 100~120fps without issue, however for CPU, it is not uncommon for an overclock i5 to have a minimum frame rate around only 70-80fps. The actual frame rate you get in games will always be limited by the lower of the two (CPU frame rate vs graphic card frame rate), so despite crossfire 7970s themselves may have no problem holding 100fps+, if the CPU minimum frame rate is only 70fps, the minimum frame rate you get in game would still be 70fps.