# Help with some harddrive cable **URL:** \ **Category:** Hardware\ **Tags:** help-and-suggestions\ **Created:** [January 19, 2024, 12:43pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060 "2024-01-19T12:43:06Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![sc88](https://forum.45homelab.com/letter_avatar_proxy/v4/letter/s/ce73a5/32.png) [@sc88](https://forum.45homelab.com/u/sc88)\ **Post date:** [January 19, 2024, 12:43pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/1 "2024-01-19T12:43:06Z")
Got my HL15 unit, with the Set D cabling. Apologies for the dumb question, what is the P4 meant to connect to? I got 4 standard 7pin SATA connector (P0-P3), and a 8 pin connector (P4)? is this meant for supplying power to the SATA drives? i want to check first before i cause any damage. thanks! ![Screenshot 2024-01-19 at 12.41.57](https://forum.45homelab.com/uploads/default/original/1X/3cff2f70dcaa2c72296069618e3d5632c60f7c35.jpeg) ![Screenshot 2024-01-19 at 12.42.10](https://forum.45homelab.com/uploads/default/original/1X/d34b55354a50ed0762a30e954371b2ade65e4372.jpeg) ---
**Author:** ![DigitalGarden](https://forum.45homelab.com/user_avatar/forum.45homelab.com/digitalgarden/32/1785_2.png) [@DigitalGarden](https://forum.45homelab.com/u/DigitalGarden)\ **Post date:** [January 19, 2024, 1:25pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/2 "2024-01-19T13:25:25Z")
P4 is called a SAS Sideband connector. It’s optional and is used for monitoring the status of the backplane or RAID controller (not the drives). Maybe someone can give you a more complete explanation, I’ve never used it. But that is what you’d google if you want to read more. ---
**Author:** ![Hutch-45Drives](https://forum.45homelab.com/user_avatar/forum.45homelab.com/hutch-45drives/32/64_2.png) [@Hutch-45Drives](https://forum.45homelab.com/u/Hutch-45Drives)\ **Post date:** [January 19, 2024, 1:37pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/3 "2024-01-19T13:37:33Z")
As @DigitalGarden mentioned this cable is not needed and is for monitoring the backplane itself. This is not something you need to connect. all you need to connect is the 8 SATA connectors for the system to function properly. ---
**Author:** ![sc88](https://forum.45homelab.com/letter_avatar_proxy/v4/letter/s/ce73a5/32.png) [@sc88](https://forum.45homelab.com/u/sc88)\ **Post date:** [January 20, 2024, 8:58am UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/4 "2024-01-20T08:58:39Z")
Excellent, thanks for the clarification! ---
**Author:** ![tdampier](https://forum.45homelab.com/letter_avatar_proxy/v4/letter/t/ac91a4/32.png) [@tdampier](https://forum.45homelab.com/u/tdampier)\ **Post date:** [March 4, 2024, 2:37am UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/5 "2024-03-04T02:37:30Z")
I can’t seem to find any specs on the HL15 backplane at all. What is it and what cables are on the back of the backplane? The connectors on the SuperMicro motherboard for the SAS3008 appear to be 8 separate SAS 3.0 ports? Does the motherboard have SFF-8654 connectors? What connector is being used from there to the backplane? What connectors are on the backplane? The SuperMicro Motherboard you use on the build only has a SAS3008 HBA which is on 8 SATA/SAS drives? How do the other 7 drives that go in the chassis get connected? I was considering using an LSI 9300 16i HBA to connect all 15 drives to on the backplane or splitting them between that and the SAS3008 HBA on the supermicro motherboard and the LSI 9300 16i HBA. ---
**Author:** ![daemon1001](https://forum.45homelab.com/letter_avatar_proxy/v4/letter/d/ecb155/32.png) [@daemon1001](https://forum.45homelab.com/u/daemon1001)\ **Post date:** [March 4, 2024, 3:34am UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/6 "2024-03-04T03:34:33Z")
Hi @tdampier, Take a look at this thread for specifics on the Supermicro board included in the full build. The backplane connectors are all SFF 8643. > [@SOLVED: What are the motherboard connectors on the full build](https://forum.45homelab.com/t/solved-what-are-the-motherboard-connectors-on-the-full-build/1148): > > What are the motherboard connectors on the Supermicro X11SPH-NCTF that is included in the full build? They are labeled I-SATA 0-3 and 4-7, and the second set is labelled L-SAS 0-7. I checked the motherboard manual, but it didn’t have any more helpful information. They both look like different types of SFF connectors, but I was wondering specifically what they are called. Thanks. Kevin ---
**Author:** ![DigitalGarden](https://forum.45homelab.com/user_avatar/forum.45homelab.com/digitalgarden/32/1785_2.png) [@DigitalGarden](https://forum.45homelab.com/u/DigitalGarden)\ **Post date:** [March 4, 2024, 3:42am UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/7 "2024-03-04T03:42:39Z")
The backplane has four SFF-8643 connectors. The X11SPH motherboard in the full build has two SFF-8643 ports connected to an onboard LSI 3008 controller supporting 8x SAS3 12Gbps drives and two SFF-8087 ports connected to the C622 chipset supporting 8x SATA 6Gbps drives. The full build uses what they list on the web site as cable set “B”, which is two SFF-8643/SFF-8643 cables and two SFF-8643/SFF-8087 cables, to connect the motherboard to the backplane. The backplane only has 15 drive bays, so one of those 16 lanes goes unused/unavailable. What that means is that if you are using only SATA drives in a full build, you don’t need any additional HBA. And also that you can mix a combination of SATA and SAS drives up to eight SAS drives without an additional HBA. You only need an HBA expansion card if you plan to run more than eight SAS protocol drives. ---
**Author:** ![Hutch-45Drives](https://forum.45homelab.com/user_avatar/forum.45homelab.com/hutch-45drives/32/64_2.png) [@Hutch-45Drives](https://forum.45homelab.com/u/Hutch-45Drives)\ **Post date:** [March 4, 2024, 12:52pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/8 "2024-03-04T12:52:27Z")
Thanks, @DigitalGarden, couldn’t have said it better myself @tdampier, if you have anymore questions please feel free to ask me. ---
**Author:** ![tdampier](https://forum.45homelab.com/letter_avatar_proxy/v4/letter/t/ac91a4/32.png) [@tdampier](https://forum.45homelab.com/u/tdampier)\ **Post date:** [March 4, 2024, 2:59pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/9 "2024-03-04T14:59:16Z")
> [@DigitalGarden](#): > > The X11SPH motherboard in the full build has two SFF-8643 ports connected to an onboard LSI 3008 controller supporting 8x SAS3 12Gbps drives and two SFF-8087 ports connected to the C622 chipset supporting 8x SATA 6Gbps drives. The full build uses what they list on the web site as cable set “B”, which is two SFF-8643/SFF-8643 cables and two SFF-8643/SFF-8087 cables, to connect the motherboard to the backplane. The backplane only has 15 drive bays, so one of those 16 lanes goes unused/unavailable. > > What that means is that if you are using only SATA drives in a full build, you don’t need any additional HBA. And also that you can mix a combination of SATA and SAS drives up to eight SAS drives without an additional HBA. You only need an HBA expansion card if you plan to run more than eight SAS protocol drives. What is the interface from the HDDs to the backplane? SFF-8482 What are the types and numbers of power connectors on on the backplane? I read some threads about wanting to direct connect the drives individually instead of via an HBA backplane. What is the best practice? Also, what about SATA or SAS drives which have the “Power Disable Feature” Is there anything to know about how to make sure the drives spin-up if these drive types are used? Thanks ---
**Author:** ![DigitalGarden](https://forum.45homelab.com/user_avatar/forum.45homelab.com/digitalgarden/32/1785_2.png) [@DigitalGarden](https://forum.45homelab.com/u/DigitalGarden)\ **Post date:** [March 4, 2024, 4:11pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/10 "2024-03-04T16:11:41Z")
> [@tdampier](#): > > SFF-8482 Yes, of course. It’s not tri-mode. > [@tdampier](#): > > direct connect the drives individually The original 45drives pods, i believe, had forward breakout cables to each drive. There is a thread or two here from forum members rebuilding old pods. There isn’t any downside to the backplane that I know of, there is still a direct data path from each drive to the motherboard/HBA. Some backplane designs from server manufacturers use port multiplier designs that multiplex the data from multiple drives over one cable. For example, I have a Supermicro server that has 16 drives running off of just two SFF-8087 connectors. There is, as you would expect, a performance hit with that design when under heavy workload. As I described, the HL15 backplane is not a port multiplier backplane. For power disable, see; [https://forum.45homelab.com/t/hdd-power-disable-feature-pin-3/404](https://forum.45homelab.com/t/hdd-power-disable-feature-pin-3/404) I’ll let Hutch or someone answer about the power distribution. ---
**Author:** ![Hutch-45Drives](https://forum.45homelab.com/user_avatar/forum.45homelab.com/hutch-45drives/32/64_2.png) [@Hutch-45Drives](https://forum.45homelab.com/u/Hutch-45Drives)\ **Post date:** [March 5, 2024, 12:31pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/11 "2024-03-05T12:31:44Z")
HI @tdampier, the power distribution would be 4 Molex connectors on the back of the backplane. Each Molex connector would then power a group of 4 HDDs. The same group of 4HDDs would also share the HBA SFF cable to the HBA port ---
**Author:** ![tdampier](https://forum.45homelab.com/letter_avatar_proxy/v4/letter/t/ac91a4/32.png) [@tdampier](https://forum.45homelab.com/u/tdampier)\ **Post date:** [March 5, 2024, 3:46pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/12 "2024-03-05T15:46:52Z")
If I use a LSI 9500-16i card it only has Two SFF-8654 x8 ports and your backplane has 4x SFF 8643(“Mini SAS HD”) ports. Note: I will also more than likely use the SUPERMICRO MBD-H12SSL-NT-B ATX Server Motherboard which has no SAS3008 because I am going to use the LSI 9500-16i Gen4 card instead. Do you provide a cable breakout for this in your build for just HL15 Chassis & Backplane? I am planning on using the following power supply: Seasonic Electronics Vertex GX-1200 1200W 80 Plus Gold ATX (Dimensions: 160 mm (L) x 150 mm (W) x 86 mm (H)) - so i will dedicate a single PSU port per the 4 molex connectors on the Backplane. ---
**Author:** ![Hutch-45Drives](https://forum.45homelab.com/user_avatar/forum.45homelab.com/hutch-45drives/32/64_2.png) [@Hutch-45Drives](https://forum.45homelab.com/u/Hutch-45Drives)\ **Post date:** [March 7, 2024, 12:32pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/13 "2024-03-07T12:32:00Z")
You would need Set F cables which could be 2 SFF 8643 to 1 SFF 8654 Cable. this set would include 2 of these cables ---
**Author:** ![tdampier](https://forum.45homelab.com/letter_avatar_proxy/v4/letter/t/ac91a4/32.png) [@tdampier](https://forum.45homelab.com/u/tdampier)\ **Post date:** [March 7, 2024, 2:16pm UTC](https://forum.45homelab.com/t/help-with-some-harddrive-cable/1060/14 "2024-03-07T14:16:53Z")
Great thanks for the clarification