[SOLVED] Can i run 2 gpus on gigabyte z370p?

[Kosm0]

Hi
I am running a z370p gigabyte motherboard with a 1070 gpu. I just bought a 3090rtx and I would like to connect it to the same motherboard. I will use my 1070 for gaming and my 3090 for mining.


Here and there I read that if I put my 3090 and the 1070 on the board it would split the efficiency of the 2 gpus. Is this true or can I just connect the 3090?

Kind regards,
Kosmo

 

[sizzling]

I believe for mining you can but each gpu will run at x8 pcie lanes and not x16. That may hurt the performance of the 3090.

 

[Kosm0]

I believe for mining you can but each gpu will run at x8 pcie lanes and not x16. That may hurt the performance of the 3090.

So would you suggest me to take out the 1070 and just run the 3090?

And why does it split to x8 pcie lanes? There are 3 x16 lanes. There are mining rigs with 10 gpus connected to a motherboard, is it the same with those?

 

[sizzling]

So would you suggest me to take out the 1070 and just run the 3090?

And why does it split to x8 pcie lanes? There are 3 x16 lanes. There are mining rigs with 10 gpus connected to a motherboard, is it the same with those?

That motherboard chipset only supports CPU’s with 16 pcie lanes so it has to split them when multiple devices are installed. For mining it wont be a problem but I assume you didn’t buy a 3090 to do mining.

 

[Zerk2012]

So would you suggest me to take out the 1070 and just run the 3090?

And why does it split to x8 pcie lanes? There are 3 x16 lanes. There are mining rigs with 10 gpus connected to a motherboard, is it the same with those?

The 2 and 3rd X16 slots only run at X4 speed.

1. 1 x PCI Express x16 slot, running at x16 (PCIEX16)
   * For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16 slot.
2. 2 x PCI Express x16 slots, running at x4 (PCIEX4_1/PCIEX4_2)

 

[Kosm0]

That motherboard chipset only supports CPU’s with 16 pcie lanes so it has to split them when multiple devices are installed. For mining it wont be a problem but I assume you didn’t buy a 3090 to do mining.

I dont understand this completly. Are there cpus that support 32 lanes so that I could run them both?

I actually did buy it just to mine. So will the 3090 be able to fully perform if the cpu has to split the pcie lanes?

 

[sizzling]

I dont understand this completly. Are there cpus that support 32 lanes so that I could run them both?

I actually did buy it just to mine. So will the 3090 be able to fully perform if the cpu has to split the pcie lanes?

Nothing on that cpu socket supports more than 16 lanes. I believe other platforms supported higher but I never had a need to look into them. At this point you might as well try it and see.

I am surprised the 3090 makes sense for mining given its small compute performance increase over the 3080 and massive price premium. I would have thought 2 of any other 3000 series would have been better than a single 3090 but I could be wrong.

 

[Kosm0]

Nothing on that cpu socket supports more than 16 lanes. I believe other platforms supported higher but I never had a need to look into them. At this point you might as well try it and see.

I am surprised the 3090 makes sense for mining given its small compute performance increase over the 3080 and massive price premium. I would have thought 2 of any other 3000 series would have been better than a single 3090 but I could be wrong.

True, but they are sold out everywhere, only 3090 was left and it was to get into mining. I will look into making a rig of 3060 or 3080

 

[Kosm0]

The 2 and 3rd X16 slots only run at X4 speed.

1. 1 x PCI Express x16 slot, running at x16 (PCIEX16)
   * For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16 slot.
2. 2 x PCI Express x16 slots, running at x4 (PCIEX4_1/PCIEX4_2)

So if I would put 1 gpu in the 2nd or 3rd x16 pcie lane, it would only at x4.
If I would put 1 in the 1st x16 and 1 in the 2nd x16 they would run at x8 each.

What would happen if I put one on the 1st, 2nd and 3rd?

 

[Kosm0]

I believe for mining you can but each gpu will run at x8 pcie lanes and not x16. That may hurt the performance of the 3090.

If I use a riser to connect my 3090, will it also run at 8x? For example they use Gigabyte GA-H110-D3A which has 1 pcie 3.0 x16 and 5 pcie 2.0 x1. In rigs they just use risers to connect and all gpus can run. I dont understand how this works

 

[Zerk2012]

So if I would put 1 gpu in the 2nd or 3rd x16 pcie lane, it would only at x4.
If I would put 1 in the 1st x16 and 1 in the 2nd x16 they would run at x8 each.

What would happen if I put one on the 1st, 2nd and 3rd?

Yes limited to X4 speed in any slot except the top one. That's why the board only supports Xfire and not SLI

EDIT buying a 3090 to mine with is not a good idea at all. For that price you could build a mining PC and use like 3 RX 570's

 

[Kosm0]

Another small question

So if I connect my 2 gpus ont he 16x slots they will both run at 8x.

But if I connect 1 to the upper 16x slot and i connect one via a riser to a 1x slot, will the first then be 15x andt he latter 1x or still both 8x?

 

[Zerk2012]

Another small question

So if I connect my 2 gpus ont he 16x slots they will both run at 8x.

But if I connect 1 to the upper 16x slot and i connect one via a riser to a 1x slot, will the first then be 15x andt he latter 1x or still both 8x?

Your still not understand the way your board works. Also for the last time if you bought a RTX 3090 for mining sell it and make some money. You can buy a completely new PC for just mining and have it run 24/7 for the price of that single card.

Edit you need to read up on mining,

In general you could use a PC like this and add a couple risers, add 3X RX 570's from ebay their like 100/125 bucks each, down clock and under volt them, make a case the real only thing is mounts for the video card freaking wood would do. All in about 6 / 7 hundred bucks you can run windows 10 not activated for free.

PCPartPicker Part List

Type|Item|Price
:----|:----|:----
CPU | Intel Celeron G5900 3.4 GHz Dual-Core Processor | $48.17 @ Amazon
Motherboard | Gigabyte B460M DS3H Micro ATX LGA1200 Motherboard | $81.98 @ Newegg
Memory | G.Skill Ripjaws V Series 8 GB (2 x 4 GB) DDR4-2400 CL15 Memory | $40.98 @ Newegg
Storage | SanDisk SSD PLUS 240 GB 2.5" Solid State Drive | $34.90 @ Amazon
Power Supply | SeaSonic CORE GM 650 W 80+ Gold Certified Semi-modular ATX Power Supply | $80.98 @ Newegg
| Prices include shipping, taxes, rebates, and discounts |
| Total (before mail-in rebates) | $302.01
| Mail-in rebates | -$15.00
| Total | $287.01
| Generated by PCPartPicker 2021-01-09 19:57 EST-0500 |