The mounting hole pattern is not the real problem. The hole pattern on both tray and board match perfectly.

The case size, to short(?) does not allow them to align.

After digging up the info available on the board it seems Inel made it for Dell.

References to it being used in the XPS series were found also.

However. There was a point when Dell went away from a more "custom" case for the XPS to a case closely resembling the Dimension.

Thus my follow up question. Which has not yet been Mod approved to appear, about Dimension case size(s).

0ldsch00l,

Unfortunately, I have no information on which Dell case the motherboard will fit it. My database does not provide me with this information.

https://www.intel.com/content/www/us/en/support/boards-and-kits/desktop-boards/legacy-intel-desktop-boards/intel-desktop-board-d955xcs.html

Most all Dell cases DO NOT USE standard mounting so I would say none.

Dell tends to mount the board into a tray and then slide in.

 BTX on the other hand uses holes and spacers in SPECIFC locations.

0ldsch00l,

I hope this information helps you out.

The 9100 BTX Sleek design case is a mid size tower. Below are the dimensions.

Height 44.45 cm (17.5 inches)
Width 16.764 cm (6.6 inches)
Depth 44.45 cm (17.5 inches)

Mitac-designed, BTX case

Thanks again Jesse L.

Comparing those measurements to my 9100 seems to show me it is a mid size.

That answers that.

Would it be possible to get me the measurements of the BTX /XPS or Dimension full size towers?

The current model I have does not have the removable mobo tray, At  least as far as I can see.

There are no "standard"  mobo stand-offs as is the norm on all cases today.

There are actually stamped risers with threaded holes where screw in stand-offs would normally be.

The same with the processor heat sink,, fan shroud, and fan.

Which draws air directly from the front of the case as opposed to the more normal "fan directly on heat sink" setup.

Try motherbnard.org or something like: BTX form factor guide. My Opti 380 desktop(DT) uses a 10.5"x 12.8" mobo. It is std. size. I believe there were 2 smaller size BTX mobo  made: nano & pico. The 380 will accept all 3 sizes. If it's true what another visitor said about non-std bolt mntg, Then use a diff tray also. Mobo dimensions can be quickly found on Wiki...type in BTX motherboard wiki. I also believe that all of the "tower" versions of 3 digit Dell's (380,580,780,980) will fit your board.. Keep looking.

Thanks. Will follow up on those links.

My board measures 11.5 x 12.75 +/-

Sounds like you are correct on Dell`s naming scheme. 4 digit names may be mid-size while 3 digit are full size.

The bolt pattern and spacing are identical to the board currently in the 9100 case.

It is only the overall size of the D955XCS that will not allow it to fit.

I wish Dell would have used some SATA 3 boards in BTX.

The D955XCS board  has 4 SATA 3 ports.

A total of 8 SATA ports available.

It is a BTX board. Just unable to confirm if Dell ever used it and in what case.

Quote direct from PDF manual.

"Up to eight Serial ATA channels (one device per channel)

— Four RAID capable Serial ATA (3.0 Gb/s) connectors (black) via the

ICH7R

— Four RAID capable Serial ATA (SATA) connectors (blue) via the discrete

controller"

No such thing as socket 755.   LGA 775, also known as Socket T.  

 I don't think INTEL D975XBG Fits.

Forgot to add that the E8500 is a Core2 Duo.

Also Optiplex boards are out as they do not have enough PCI slots available for my needs.

After narrowing it down to only the XPS 700/720 case fitting this board.

Then having no luck finding one.

As well as seeing old listings for ones where shipping alone made it cost prohibitive. Have decided to attack this from another direction.

I am now looking for a BTX board that will accept a Pentium E8500 3.16 GHz Socket 755.

A minimum 8 Gig of RAM. Preferably 4x2 as I already have the memory.

Needs to fit in a Dimension 9100 tower. Which is a mid-size case.

Thanks for any assistance.

My mistake on the 755 vs the correct 775.

Too many numbers swimming through my head.

Are both those pics of the D975XBG ?

Ran across the bottom shaped board on Ebay.

That board accepts 8 Gigs. 2x4

Though there are posts here on the Dell site with Users reporting 16 Gig works.