Or lay a motherboard on top of the cable running flat out, this would represent a real world scenario.
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Part Flexible PCIe risers
- Thread starter iFreilicht
- Start date
Couple new cables released by Thermaltake that actually look REALLY nice. Up to 1m in length and sounds like the 30mm cable will cost around 60 AUD
Yeah I don't even know. I presume it would act as a replacement in some crazy case they've released or something. That being said, some of the attention to detail of the cables is quite nice and if they've managed to get a PCIe signal to travel 1m on these units, I reckon they must be decent. The longest 3M you can get is only 500mm.
Probably for their case that's the size of a small house.
For real, though, couldn't we make pretty good risers with thunderbolt 3? Seems like a pretty obvious choice for something like this.
4x would be fine, it's good enough for eGPUs. Why would one need two controllers? EDIT: I am dumb, one on each side of the riser. Any idea on the ballpark of the JHL6540 (which seems to be the alpine ridge controller)?
EDIT2: Oh man, a single TB3 cable of 0.5m length already costs like 20 bucks. Better get a LiHeat riser at that price.
EDIT2: Oh man, a single TB3 cable of 0.5m length already costs like 20 bucks. Better get a LiHeat riser at that price.
Anyone already experienced the Moddiy powered riser ?
I heard somewhere that the 30cm length was causing some issues, and could work if configured as Gen 2.
I heard somewhere that the 30cm length was causing some issues, and could work if configured as Gen 2.
3.0 has effectively double the bandwidth. For gaming, the difference is only slight, around 10% for the 1080 at 1920x1080, but that gap will reduce as framerate reduces (unlikely to be a problem with a 1060).
The tricky part here is thin-ITX's PCIe slot is not intended to provide the 75W a purely bus-powered card expects to draw. For the 1060, this should* not be an issue as it has external PCIe power connectors which the card will draw from preferentially. Your only remaining problem would be that you now need a second PSU to power the GPU, separately from the thin-ITX board which will be powering itself from the 19V input. People have mostly addressed this by using a single large 19V brick connected to the thin ITX board, then using the 19V output on the thin ITX board (note, some boards lack this, or just have pads rather than a convenient connector) to power an internal DC-DC PSU that powers the GPU. This runs them from the same ground, so avoids ground plane mismatch issues.
The only drawback is that the DC-DC PSU will be powered continuously whenever the 19V br9ck is plugged in, which can waste power. This can be solved by adding an electronic switch to the DC-DC PSU so that it only powers on when the thin ITX board is on (like the old trick of jumping the ATX plug with a paperclip between pins 16 & 17, except you instead use a transistor triggered by the +5VDC pin on the front-panel connector). This is likely an unecessarry complication, as the GPU will not power on unless it sees voltage from the motherboard via the PCIe slot, so will be drawing effectively nothing from the DC-DC PSU.
* There are a handful of cards like the RX 480 that will try and draw a full 75W from the PCIe slot anyway. In that case, a riser would need to be used that cuts the power traces from the motherboard and connects them to the DC-DC PSU. In this case, using a switch to turn the DC-DC PSU on and off would be required, to avoid the GPU being an an abnormal state of being fully powered on but having no data connection to the motherboard.
@EdZ Thank you very much for your input.
- Just in case, would it possible to mod the GPU bios to force it to draw only 25W from the PCIe slot ?
Is it not this way (sofwtare solution, not hardware) AMD solved the RX480 issue ?
- By using the onboard 7.4mm barrel connector, is there any risk to get very close to the maximum wattage ratings and burn the connector ?
I expect my system to draw 200W maximum.
The idea was to use a modded Dell brick with two 7.4 barrel connectors, one for the motherboard, the other for the DC-DC board.
This may be a way to avoid overloading the single 7.4 barrel connector of the motherboard ? What do yout think ? Is it necessary ?
- If I were to use a single 19V brick plugged in the sole motherboard barrel connector, how can I be sure that the 19V 2Pin inlet can also be used as passthrough ? This was my initial idea as well but it is not specified in the mobo manual.
http://asrock.pc.cdn.bitgravity.com/Manual/H110TM-ITX.pdf (p. 20)
- In any case, the DC-DC board is synced with the motherboard using an ADD2PSU pcb, thanks to a Sata power to molex adapter.
This has been reported to work.
The RX 480 modification just slightly pulled the current draw back within the 75W (or rather, 66W from 12V alone) spec limit. The power draw distribution is mostly fixed by the physical connection of the VRMs to power planes on the card PCB.
short version: no. A suer BIOS mod cannot remove a card's reliance of slot power.
200W at 19V is 10.5A, which should be fine.
A single barrel connector should be fine for 200W
If the 2pin connector is present, then it is linked to the same power planes as the DC barrel. This is part of the Thin ITX specifications (it;s intended to be a DC in plug, but in practice it's just a different way to connect to the same power components that the DC barrel connector links to. There are no diodes to enforce directionality.
The Add2PSU works fine, it's just excessively large.
Thanks a lot, precious input !
Enclosed is a detailed overview of a stock GTX 1060 6GB consumption.
The GPU pulls more than 60W from the PCIe x16 slot under load.
Is it going to step down its PCIe load to 25W and pull an extra 35W from the 12V PEG all by itself ?
A bit like a modded riser, in which case the GPU balances all the load on the sole 12V PEG ?
In that case, what a powered riser is useful for, except running GPUs without external PEG connectors ?
Enclosed is a detailed overview of a stock GTX 1060 6GB consumption.
The GPU pulls more than 60W from the PCIe x16 slot under load.
Is it going to step down its PCIe load to 25W and pull an extra 35W from the 12V PEG all by itself ?
A bit like a modded riser, in which case the GPU balances all the load on the sole 12V PEG ?
In that case, what a powered riser is useful for, except running GPUs without external PEG connectors ?
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