2

Without disassembling enough of my two running self-built desktop PCs to be able to measure them in millimeters, I'm trying to find out the spacing of the pins on the standard TPM-M (also called 14-1 because one pin is blocked) motherboard connector. It's likely either 2.54mm, 2.0mm, or 1.27mm - I think. I have no discrete TPM modules, connected or unconnected, to take measurements from instead.

I've tried Googling but I haven't had any 100% positive luck. The closest I found is the top search result from this Google search, which when followed leads here, at which the top result is for 2.54mm Pin header Double Row Pin Header Right Angle S.M.T Type, however, the second Google search result leads here (same site) on which the second item listed is 1.27 Pitch Dual Rows Pin Header - H1.0 Right angle type pin header connector - P/N.Y01410-12R-RA-XP.

I'm not trying to buy any of these items - I'm trying to find the correct pitch in order to either buy or build the correct short extension cable since I have an obtrusive card in the PCIe slot which would likely interfere with using a discreet TPM module and moving the card to another position isn't an option. This particular desktop doesn't have a processor with a built-in TPM either.

Also, I would likely encase the TPM module, once I get one for a not crazy price.

Cheers and thank you!

Update 1: The (not what I'm looking for) 20-pin TPM connector pin spacing appears to be 2.54mm, as evidenced here, which doesn't mean anything except just another piece of data.

Update 2: I've come a little closer to what I was looking for. I decided to try re-wording my Google search once more, and lo and behold, the answer was the second search hit leading right back here to superuser.com. The second to the last answer by @user2850988, currently with 5 upvotes, has related information, but sadly the spacings listed are only for TPM-L and TPM-S, not TPM-M:

Please note that on the mechnical part there at least 3 different types. See as well for the electrical part: LowPinCount-Bus (LPC bus).

pincount (14pins for M, 19 out of 20 pins for L, 17 out of 18 pins for S)

pinspacing: 2,54mm for TPM-L and 2mm for TPM-S. TPM-S has the "ident-pin" (the "missing one/stuffed hole") on 3rd last column, TPM-L has the ident pin on the 2nd last column.

edited Jan 24 '19 at 20:35 zx485

answered Jan 24 '19 at 15:20 user2850988

roirraW 'edor' ehT
  • 29
  • 1
  • 6
  • You are aware that every processor that supports Windows 11 supports a fTPM that all AMD and Intel supported processors support? Outside of that, your motherboard likely supports only specific discrete TPM, knowing the pin pitch won’t be helpful. – Ramhound Aug 04 '21 at 22:51
  • 1
    This is not regarding Windows 11, and the desktop in question doesn't have a processor that supports fTPM. This motherboard supports TPM-M, also known as 14-1 for the overall pin count, minus one pin in a particular place that's blocked on the appropriate add-on TPM module. I'm aware of the TPM-M (14-1) type TPM modules I have a choice from to buy. The problem is that I need to use a cable to go between the motherboard and the TPM module, to physically bypass a PCIe card that I have in a slot right next to the TPM-M connector on the motherboard. I need to know the spacing to get correct 1. – roirraW 'edor' ehT Aug 05 '21 at 01:42
  • What is the make and model of the motherboard in question? – Andrew Morton Aug 05 '21 at 16:49
  • Thanks Andrew, the answer is MSI X99A SLI Krait Edition (I believe MS-7885), although I left it out of the original question on purpose because the answer will likely apply to all 14-1 connectors on all manufacturer's motherboards. They seem to all be the same physically, not counting that Asus has an additional 14-1 motherboard connector that has the blocked pin in a different spot, but a cable that worked as an extension on one will likely work as an extension on many different manufacturer's motherboards. In my case, I still have to use an MSI 14-1 TPM-M module MS-4136. – roirraW 'edor' ehT Aug 05 '21 at 17:48
  • I wish there was some way to get @user2850988 's attention, although they might not know the answer. – roirraW 'edor' ehT Aug 13 '21 at 21:22

1 Answers1

1

On my Asus motherboard it has half the spacing of the USB headers next to it.
USB headers are certainly 2.54 mm, so 1.27 mm is the answer.

Obviously I don't know if there are variants with other spacing. Your motherboards might be different.
It is next to impossible to find this information online for the 14-pin TPM header. (The 20-pin has a spin-spacing indicator as suffix in the name.)

Tonny
  • 29,601
  • 7
  • 52
  • 84
  • Hi @Tonny. Would you mind letting me know which Asus motherboard model you have? Thank you! – roirraW 'edor' ehT Aug 05 '21 at 13:48
  • I've got a Asus Prime X470-Pro. I was trying to find a 14-1 TPM myself and I also discovered what a mess this is... (My Ryzen has fTPM, but I prefer a discrete one. fTPM can loose keys during a Bios update which would really suck in my case.) – Tonny Aug 05 '21 at 13:58
  • Thanks, I appreciate the information. I don't know if this is allowed, but this is the best bet I've found for Asus' TPM-M module: https://www.shopblt.com/cgi-bin/shop/shop.cgi?action=thispage&thispage=01100300U033_B3F8915P.shtml&order_id=757540126&sitem=B3F8915. $10.82 U.S., 5,504 pre-ordered by users, and they have 6,540 stock incoming, and expected ETA for an order today is 9/20/2021. Note this is changing fast as 24 hours ago ETA was 9/4. I don't feel completely secure that the 14-1 TPM-M connector has half the spacing of USB headers - maybe 2.0mm so I'll wait for other confirmation. – roirraW 'edor' ehT Aug 05 '21 at 14:29
  • 1
    @Tonny Your answer is incorrect. TPM-M headers have a pitch size of 2.0mm. Please do not state your answer authoritatively when you're making a speculation. – user156256 Oct 07 '21 at 16:19