Covering GPU pins with sticky note to force gen3 x8 mode. How many pins to cover properly?

rynz101

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Feb 1, 2013
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My original question was asking about how many pins should I cover up on my graphics card to force it to run in a x8 mode on a x16 slot. With no option in my bios to change my pcie bandwidth I wanted to do it manually with some tape, covering up the extra pins.

The answer is 2x49 pins. 49 pins on both sides. This includes the pins on the little nub that give the card power. So I need to tape up all the pins until only 49 are exposed on each side. This will make the card run in x8 mode. Here is a link to where I got my information- http://www.interfacebus.com
Scroll down a little to where it says "pci express pinout" and choose a link.
We can close this question :D

I'll recap the story attached to my motive for wanting to do this...
I have a riser cable that seems to only run stable on a gen2 x16 bandwidth. Card crashes on anything faster when using my riser cable. Since I can't use my primary gen3 x16 slot, I have been using my second pcie gen2 x4 slot. It's been very stable and performing better here actually in the x4 slot. I don't like the idea of my card running on a gen2 x4 slot though. So my plan is, since my cable only wants to work at a gen2 x16 speed, i am going to put the card back in to my gen3 x16 slot and run it in a x8 configuration. gen3 x8 is similar in speed to a gen2 x16 slot. Hopefully getting the card stable again back in my gen3 slot. This will allow me to use my graphics card with out a bottleneck in the pcie slot that it was meant to be installed on and i'll get to do it using my riser cable. Gen2 x4 was very impressive playing games on and I honestly didn't see any noticeable differences but its a gen2 x4 slot. I would rather run the card in a gen3 x16 slot in x8 mode if I can.
There could be several reasons why my riser wont run in a gen3 x16 @ 16x. I think it's just interference. Getting stable in a slower pcie slot kinda proved that to me. I think gen3 x16 is to finicky given the interference i'm probably getting.
 
I'm not sure your thinking is correct. Even if you can make it run 8x, it's still going to be gen3.

Next is a question which I've never been able to find an answer to, do cards actually use all 16 lanes if available, or do they only use as many as they need? So, maybe reducing it to 8x won't make any difference to how many lanes it uses anyway.
 

USAFRet

Titan
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Please, a link to this article?
 

USAFRet

Titan
Moderator


I would ask the good people at Puget Systems about that 5 year old article.
 

rynz101

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Feb 1, 2013
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Ok, ok. Seems some confusion has been made.
I have a gen3 x16 slot for my primary pcie and a second gen2 x4 slot. My card is plugged into the gen2 x4 slot because it wont run on my riser, (stable) in my primary gen3 x16 slot. I think having my card in my second gen2 x4 slot is probably not a very good idea so what I want to do is put my video card back in to my primary gen3 x16 slot with some covered pins so it will run in gen3 x8 mode. gen3 x8 is really close to gen2 x16 speeds and thats where my card will run stable on my riser cable so i wanna try running my card in x8 mode on the gen3 slot. I need to know what pins to cover up to do this.
 

rynz101

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Feb 1, 2013
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You know what would be great? If I could find a chart that shows the saturation level or total bandwidth a list of cards could pull so i can see how badly a gen2 x4 is bottle necking my rx 480. I bet its more dramatic if you have a higher end card but i have a rx 480 and I want it to do 1080p 60fps... some times 1440p super resolution. gen2 x4 cant be that bad with this card trying to do 1080p @ 60fps. Even if it didn't bother the card, which it really doesn't. I don't notice anything but i bet if I tried to play in higher resolutions or demanded crazy things like 8x AA EQ or some none sense.. it probably would start to show that its on a gen2 x4 slot.
If I could look at a chart and I read it and it said something like "rx 480 pulls this much pcie bandwidth and at said speed, your looking at a performance loss of XXX" Then I could be like well, oh! it doesn't matter unless im trying to blast 1440p on some gnarly settings. cool. i'll leave it in my gen2 x4 slot hehe

I don't know that though? so i wanna try the gen3 x8 sticky note, cover up the pins mod for x8 mode and try it because I really wanna use my riser cable and it seems to only work fine in gen2 x16 or the similar gen3 x8 mode
 

USAFRet

Titan
Moderator


No, no confusion.
Ask Puget exactly which pins they covered up to achieve this.

If indeed dropping it down to x8 is the actual solution to what you need it to do.