Bitcoin Forum

Step 1: Take down that wall!

Seriously. I did this, expecting i'd have to jump a pin on my GPU to make it detect. But nope. It works just fine! The GPU autodetects the bandwidth of the slot and runs at 1x speeds.

https://i.imgur.com/s7hk0cy.jpg

Works just fine.

https://i.imgur.com/Vk15EG9.jpg

No need for these risers anymore!

By the way, if anyone wants to know. The method I used to take it out is by putting a cut-out piece of a PCI connector in the slot to protect the pins, and then using a hot soldering iron to melt off the wall. Took about 5 minutes.

Now, I have two 7870's running on a $30 Pentium 4 board. :P Light mining rig base. 380 kh/s stable with mining scrypt.

Really? I just use an exacto knife. I always assumed you riser guys were using them to fit more cards to a board than otherwise possible, not that you just didn't know how to take the end off a PCIe slot.

Not a lot of people know about it, and there's next to no official documentation that makes this clear.

risers do the exact same thing electrically, without invalidating the warranty on your motherboard.

The main reason we use riser is to spread the cards so that they are not too hot and we can use more slots.

http://lifehacker.com/5951156/convert-a-pci+e-x16-video-card-to-fit-a-x1-slot-with-a-diamond-cutting-wheel  ;)

But your method is better since you don't damage the GPU.

Well, that method did not damage the GPU, it just got modified. Either way, you would need to modify the GPU or the motherboard. Or just use riser.

I think the OP is pointing out that you can use much older hardware (and no warranty issues if so) to do some mining without waiting for the mail from China with the risers in it (or paying through the nose for US shipped ones).  This is a good way to repurpose older hardware that you may have lying around.

I have access to a few older PC's that only have X1 slots, and I may buy some of the 7790's on sale now at newegg and use this to mount them properly in the case.  Thanks for the idea :)

Finally, someone got it. :P

Thx for the tip

Dude well done ! Smart move and it worked.

Why a 7790? is the price point just right for that gpu? the power draw of a 7850/7950/7970 too much for an old LGA775 mobo? limited by PSU capacity\connections? Sorry for all the questions but there is a bunch of old hardware in my basement begging for new/used GPUs.

I've drawn 200+ watts per card on this mobo. THing is none of the power is actually ever drawn through the mobo. It's through the PCI-E plugs that go straight to your power supply.

So hash rate will not suffer if a 7950 PCI-e 3.0 slides into an old mobo only capable of PCI-e 2.0 or even 1.0?

Yes. No problem whatsoever. You can even put it to a 1x slot that's PCI-E version 1x and it won't suffer.

This is because the GPU is a computer in it's own right, and it's running it's own computer program in it's own ram space and such. consequently, all that needs to pass over the pci-e lane is the program to run on the card and then the results of the program.

I've used a 7950 with an old pentium 4 mobo and I got the full 500-600 khs.

Excellent! My plans for world domination are now it full swing ;D