PCI-E power board?

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nicholasfarmer

Limp Gawd
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Apr 19, 2007
Messages
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I'm working on a Norco build using an HP SAS expander and I'm researching options to power the expander without using a PCIe slot.
The forum for the expanders exist at the URL below and with the 746 posts, some have spoken about the possibility but I did not find a solution.
http://hardforum.com/showthread.php?t=1484614

The PCIe expantion slot pinout specs can be found here:
http://pinouts.ru/Slots/pci_express_pinout.shtml

The only concern is if the card pulls the PCI clock source on pins five and six.

With this information, I'm assuming it is easy to purchase a board, soldier a PCIe 4x connector to it, add a Sata power connector to it and go.

1) ProtoBoard : $1.19
http://www.mcmelectronics.com/product/21-4590&CAWELAID=220241326
2) PCIe slot : $0.59
http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_1978289_-1
3) Reverse Sata Power cable with wires: $1.80
http://www.govgroup.com/link-depot-pow-sata-ext-sata-power-extension-cable-2215818-prd1.htm

Total of about $3.00 and you can power the board with the power supply instead of wasting a PCIe slot.
I selected the Reverse Sata power cable because it provides the 12v and 3.3v required by the PCIe slot.
I also figured the wire would be better than the board mount because of placement and cable length.

Has anyone tested this idea?
Does anyone know of such board that already exists?

Side note:
This was an interesting find. PCIe 1x to PCI slot converter.
http://www.beachaudio.com/Startech-...ium=cpc&utm_campaign=pex1pci1&utm_content=atr



*************************************************

Update to reduce reading:

I confirmed with HP that the HP SAS Expander only requires the PCIe power pins and not the clock or transmit/receive channels. This will allow the enthusiast to purchase a separate, single PCIe slot with a power plug and not waste a slot on the motherboard.

1) If you are going to use a large motherboard and don't mind placing the card in a PCIe slot, go for it.
2) Purchasing a special power slot for the adapter will allow room for another network interface or the purchase of a smaller form factor motherboard.
3) Ultimately, you can run your drives and the HP SAS expander in a separate chassis without the expensive hardware investment or extra power draw. Thanks to Pjkenned and Nitrobass24 who helped paint a picture of what is already being used for this design. Pjkenned commented on the ability to reboot the PC/Server without dealing with powering down the drives if you used the separate power supply and PCIe power adapter. I've noticed many comments on builds about the high inrush current loads and dealing with slow reboots because of delayed spin-up. This technique possibly helps resolve the issue.

If you go with #3 above, the issue of a power button is a concern but the purchase of a simple on/off (non-momentary) switch that is connected to the power supply on pins 14 and 15 will work fine.
Example:
http://www.globalsources.com/gsol/I/Pushbutton-switch/p/sm/1026835629.htm


I'm working with a few board fab companies to see if they have a single PCIe board with power for a small footprint. Many multi slot boards exists and are somewhat easy to obtain. Im working to get a very small board that can be installed up against the expansion slots.

Links to boards found:
HP noted directly that this board would work:
http://www.orbitmicro.com/global/pe-2sd1-r10-p-9375.html

Other boards that are untested but should work:
http://www.orbitmicro.com/global/pe-4s3-r10-p-2309.html?
http://www.provantage.com/supermicro-rsc-r2ut-2e8r~7SUP91Q6.htm
 
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Have you actually tried this? The problem you're going to have is that the protoboard you linked doesn't have the hole spacing to accomodate the the PCIe slot. I think you've got a great idea, but that protoboard isn't going to do it without hacking up the PCIe slot.
 
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So that's what I'm using now. The issues with that PCMIG board are:
#1 it takes forever to get (weeks).
#2 the bottom slots for the PCMIG are too tall to let the HP SAS Expander sit in the PCIe slot properly and attach to the Norco expansion slot flush.
#3 the mounting holes are sub optimal.

So there is room for improvement, but the time/ effort required to make that thing work is probably not worth it for most people. On the other hand... using the dremel I was able to fit it in the last two expansion slots freeing up a lot of room in the case for a server board.
 
Is it important to have the full ATX power connector?

I was going for something smaller that uses a Molex or Sata plug.
Also, reducing the need for more electronic components reduces the chance the "slot" will fail over time.

My plan is to have a motherboard in the system so using the ATX power connector isn't an option unless I create my own atx power pinout or install a second power supply.

I know the goal for some is to not have a motherboard in the system and use it as a Disk+Expander only. I can see spending $40+ in this scenario but $3 means $37 more I can spend on a new hard drive!
 
nicholasfarmer said:
Is it important to have the full ATX power connector?

I was going for something smaller that uses a Molex or Sata plug.
Also, reducing the need for more electronic components reduces the chance the "slot" will fail over time.

My plan is to have a motherboard in the system so using the ATX power connector isn't an option unless I create my own atx power pinout or install a second power supply.

I know the goal for some is to not have a motherboard in the system and use it as a Disk+Expander only. I can see spending $40+ in this scenario but $3 means $37 more I can spend on a new hard drive!
Click to expand...

If I understand what you're doing correctly, you're trying to create a power board to run the expander card in your OP. If it's powered directly through the PCIe bus, then no, all you need is a source of +3.3v, +12v, and Ground. The SATA power connector provides all of those and even +5v for something else if you wanted. A molex on provides +5v and +12v, so if the card doesn't use the +3.3v rail, it would work.


EDIT:
My plan is to have a motherboard in the system so using the ATX power connector isn't an option unless I create my own atx power pinout or install a second power supply.
Click to expand...

You could get an ATX splitter so you wouldn't have to have two power supplies e.g. http://www.amazon.com/Power-Supply-...8&s=musical-instruments&qid=1274284328&sr=8-2
 
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But even with the power splitter thats $8 for the splitter and still $40 for the large card with parts that can fail.

$3 for a "wires only" approach seems best but risky if the expander requires more than just voltage.

If I end up trying it Ill post an update.
 
As a minimum you will need to add a 10kOhm pull-up resistor on A11 PWRGD (Power Good) signal to +3.3V!
 
With the assumption of power conditioners being a requirement, I'm guessing my only "fail safe" option is to opt for the:

http://www.orbitmicro.com/global/pe-2sd1-r10-p-9375.html

While it is expensive when compared to simple wire and go, any power fluctuations in the power supply could spike the expander and the rest of the system.

$40 isn't as expensive as replacing an entire system because the power supply has a hiccup in the rectifier.

Interesting enough, I'm working with an HP engineer to determine the actual needs of the expander so maybe we can learn something.


***Edit:
This is the direct word from HP reguarding using the " http://www.orbitmicro.com/global/pe-2sd1-r10-p-9375.html "
*****
You may connect the SAS Expander to this card for only power.
The Expander is only a means for the controller to access the additional storage connected therefrom.
Since the expander will only access power and the main control rests with the controller, this is a plausible try.
******
As always, HP treats this as "untested" and can void the warranty.
HP also notes that connecting "non supported disks" to the Expander voids the warranty as well.

Thanks for the link Nirtobass24. I'll continue to look for some prefab parts with power regulators built in to reduce possible footprint in the chassis. Maybe we can get lucky enough to find a card just long enough to have a PCIe x16 slot and ATX power plug.
 
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You want an ATX connector on there. The whole ideas is that you can turn it on when you please and have some control over it.
 
Well, the whole point of the ATX plug is that it has the line to turn the system on and off.
 
Blue Fox said:
If you have a motherboard in the same case already, why even bother and not just use it?
Click to expand...

He probably has a ton of crap in there already. Hell, if you are using the X8SIL-F or any micro-atx mobo in your Norco you have some space and the very bottom which conveniently lines up with the SAS ports on the front.
 
Kettchxxii said:
He probably has a ton of crap in there already. Hell, if you are using the X8SIL-F or any micro-atx mobo in your Norco you have some space and the very bottom which conveniently lines up with the SAS ports on the front.
Click to expand...

Bingo! Exactly what I'm doing right now... down to the X8SIL-F :)

The trick is I have the HP SAS Expander on the modified PCMIG board with the main PSU. Using a i3-530 + X8SIL-F you can power ththat hald with a PicoPSU 150w. Front controls = SAS Expander, big PSU, and drives. X8SIL-F = remote power control for the server.

By making the system independent of the SAS Expander + disks, I can power cycle one without the other. That practically means that I can keep the expander/ disks powered and connected to the main box while still using the spare area for a functional server that I can power down completely down if I please.

Give me a day or two and I'll post pics + a writeup. I've just been testing it to make sure it keeps working.
 
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Pjkenned.... You are my hero... I knew someone had already went this route. Pictures please sir!


Bluefox: I don't want to waste a PCIe slot on a card that does not use it. A 10Gb nic can sit in there instead! Or quad gig nic for the non 10Gb flavors.
 
I too am very interested in how you are pulling this off as I maybe in the market for another controller :(
 
nicholasfarmer said:
Pjkenned.... You are my hero... I knew someone had already went this route. Pictures please sir!


Bluefox: I don't want to waste a PCIe slot on a card that does not use it. A 10Gb nic can sit in there instead! Or quad gig nic for the non 10Gb flavors.
Click to expand...

Sorry guys I was working on my X8SIL-F writeup last night and didn't get a chance to take pictures. Will do tomorrow.

BTW I came very close to going 10 gigabit but that's a huge upgrade from a cost perspective.
 
For power control on an ATX power supply, all you need is a push-button, 2 caps (e.g. 0.1uF), 2 resistors (e.g. 10k and 100k) and a D-Flip-flop to build a bi-stable latch!
Or alternatively, you could simply use a switch rather than a push-button to control the power-on signal line on the ATX power supply.
 
Have anyone made SATA Power -> PCI-E 1x/4x connector finally?
I would love to do single line connector from modular PSU directly to PCI-E connector but I still not sure how to proceed.

From what I seen at http://en.wikipedia.org/wiki/PCI_Express#Pinout I need to provide +12V to pins 1 &2 on side B and to pins 2 & 3 on side A, +3.3V to pins 8 (and 10? What aux means?) on side B and to pins 9 & 10 on side A plus ground pins 4 & 7 on side B and 4 (and 11? What PWRGD means?) on side A.

So the main questions are:
1) Is there any difference between +12V on pins 1 & 2 on side B?
2) Is there any difference between +3.3V on pins 8 & 10 on side B?
3) Should be pin 11 on side A be grounded?

If it would be simple (like I hope) I need to get (from modular PSU connector) one 3.3V wire (pin1), two ground wires (pins 2 & 4) and finally one 12V wire (pin 5). To correspond to SATA power those are pins 1,2,3 (3.3V), pins 4,5,6 and 10,11,12 (ground) and pins 13,14,15 (12V).

If anyone may helps I will provide the final guide on how to do it for community.

Thank you!
 
They are too expensive, especially for untested things.

Have anyone tried to master the SATA->PCI-E adapter/converter? Why we may need the 10k resistor?.. I have tried to find out the reference PCI-E PCB and failed... I believe that we get simple and cheap solution, don't we?

I also heard we may reset the card without dropping the power from it by sending signal to some PCI-E pin(s) - where may I read this?
 
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