Solved PCI-e 3.0 GPU + MoBo + Ivy CPU = PCI-e 2.0 ???

[Kenjiro]

Hello,

I have Asrock Z77 Extreme4 Mobo + i3 3220 Ivy bridge CPU. I've just added a Sapphire HD 7850 to this and I was expecting it to run @PCI-e x16 v3.0.

But GPU-z reports it's working @x16 v2.0

How can I fix that?

 

[bobkn]

There's a BIOS setting for the PCI-E link speed. According to your manual (p. 62 of the downloadable English version, under north bridge configuration), its default setting is Auto. You could try manually setting it to Gen 3 compatibility, in whatever fashion Asrock defines it.

 

[Dwarf]

That is perfectly normal. When your computer is not doing anything strenuous, the speed of the graphics interface drops (in my case to 1.1) because there isn't any demand graphically. However, when running a graphically intensive/demanding program, the speed will jump up to the maximum for the bus (in my case, this is 3.0). An example of a program that does this is Unigine Heaven 3.0, and if you have GPU-Z open whilst you run Heaven (you will need to change the resolution to 640x480 and deselect the Full Screen option), you will see the value change.

This feature works in much the same way as Cool'n'Quiet and SpeedStep does for AMD and Intel CPUs respectively.

 

[paulpicks21]

I have the same motherboard, but an Nvidia GPU. I didn't alter any settings after installing the motherboard and GPUz reports mine as being PCI-E 3.0

I will have a quick look in my bios to see how things are set.


Edit, scratch that, yes what Dwarf said, mine see my screenshot.


Paul.

 

[Kenjiro]

I've already set it to Gen3. No difference. There is also this:

When I open the Catalyst control center hardware tab. It also shows that Maximum Bus Setting is PCI Express 2.0 x16

Is this normal for 7850 ?

 

[Kenjiro]

GPU-Z shows @x16 1.1 when idle. Steps up to x16 2.0 when running GPU-Z render test.

 

[paulpicks21]

Did you do what Dwarf said regarding running a program such as heaven and looking at GPUz while its running?

 

[Kenjiro]

Did you do what Dwarf said regarding running a program such as heaven and looking at GPUz while its running?

Downloading Heaven now. GPU-Z render test stepped it up to v2.0 only

I'm also bugged that Catalysts shows the card's Maximum Bus Setting as "PCI Express 2.0 x16"

 

[paulpicks21]

See how it goes with Heaven, but essentially you have a PCI-e 3.0 card and a PCI-e 3.0 Motherboard so at worst its just some kind of setting wrong.

 

[Kenjiro]

See how it goes with Heaven, but essentially you have a PCI-e 3.0 card and a PCI-e 3.0 Motherboard so at worst its just some kind of setting wrong.

Yes but that affects performance. I think My 3DMark'11 scores should be higher than this with i3 3220 Ivy CPU and HD 7850 ?

SCORE P4977 3DMarks

GRAPHICS SCORE 5217
PHYSICS SCORE 4394
COMBINED SCORE 4350

Will post result with Heaven soon...

 

[paulpicks21]

I really don't know what the graphics scores should be for a 7850 in 3D Mark 11, maybe do a little google search to see what others are scoring?

 

[logicearth]

It doesn't actually affect your performance. The extra bandwidth that PCI Express 3.0 provides is not used for graphical applications. As it currently stands, 2.0 is under-utilized at this time. In order to take advantage of the extra bandwidth you need to make extensive use of GPGPU technologies.

 

[paulpicks21]

It doesn't actually affect your performance. The extra bandwidth that PCI Express 3.0 provides is not used for graphical applications. As it currently stands, 2.0 is under-utilized at this time. In order to take advantage of the extra bandwidth you need to make extensive use of GPGPU technologies.

Good point, I was thinking about it earlier in the thread but got tied up in looking into if it was actually running at 3.0 for him.

Not that its important, but here is a screenshot of when I have Heaven running in windowed, as you can see it's changed from 1.1 at idle to 3.0 just as Dwarf said it would.

 

[Kenjiro]

I really don't know what the graphics scores should be for a 7850 in 3D Mark 11, maybe do a little google search to see what others are scoring?

5200 graphics score seems to be absolute minimum for my rig. When you score 5199, 3D Mark website shows a red alert message: "It looks like your PC should score better."

So being just above the alert level (Not all the time, some runs trigger the alert) makes me think that there is something wrong with my computer

 

[Kenjiro]

Good point, I was thinking about it earlier in the thread but got tied up in looking into if it was actually running at 3.0 for him.

Not that its important, but here is a screenshot of when I have Heaven running in windowed, as you can see it's changed from 1.1 at idle to 3.0 just as Dwarf said it would.

What do you get when you run the GPU-Z render test? up to v3.0 from 1.1 ? or just to v2.0 as I do?

 

[paulpicks21]

I really don't know what the graphics scores should be for a 7850 in 3D Mark 11, maybe do a little google search to see what others are scoring?

5200 graphics score seems to be absolute minimum for my rig. When you score 5199, 3D Mark website shows a red alert message: "It looks like your PC should score better."

So being just above the alert level (Not all the time, some runs trigger the alert) makes me think that there is something wrong with my computer

Well I don't think you have anything to worry about, I googled your card, seems most score between 5000-5500 tops. Don't forget you have the 1GB version, do they take that into account on the alert level?

I would forget about it, it's within the margins and only a benchmark, as long as it plays games well then it's doing its job.

 

[paulpicks21]

Good point, I was thinking about it earlier in the thread but got tied up in looking into if it was actually running at 3.0 for him.

Not that its important, but here is a screenshot of when I have Heaven running in windowed, as you can see it's changed from 1.1 at idle to 3.0 just as Dwarf said it would.

What do you get when you run the GPU-Z render test? up to v3.0 from 1.1 ? or just to v2.0 as I do?

Give me a min to test.


Edit, tested, goes straight to 3.0 as soon as the test starts.

 

[Kenjiro]

Mine still goes up tp v2.0 while running Heaven

 

[paulpicks21]

Well as Logicearth has already pointed out, you will see no increase in performance so don't worry about it too much.

I know this as a fact as I have just switched from i7 2600k P67 PCI-E 2.0 to i7 3770K Z77 PCI-E 3.0 and my scores in 3D mark 11 and Heaven have remained the same with the same GPU.

Although it would bug me as to why it's not running at 3.0 and I can understand you want to get what you paid for.

 

[Dwarf]

Take a look at the following links. Scroll down to the section Expansion Options and note what it says for PCI Express Revision.

My CPU: ARK | Intel® Core

Your CPU: ARK | Intel® Core

According to the above, your CPU only supports v2.0 whereas mine supports v3.0.