I am re-building an old Dell fitted with an E139761 Intel motherboard. Can anyone point me to the info regarding the motherboard to front panel connections? i.e. HDD LED, Power Switch, Reset

Is this your board?

http://users.ece.gatech.edu/~hamble...

Yes, it's been lying around for sometime since the case was used for an upgraded pc for my daughter. I have mislaid the note I made of the original front panel connections! I'm now trying to fit this board to a non Dell case.

Was the original connection from the Dell front panel a single plug or were there separate connecting wires? If it's the former post back the Dimension model number. I probably have some around I can check.

If the wires connected to the motherboard individually their proper postitions should be marked on the motherboard.

The original connections were via a single plug onto a 16 pin double row header (8 rows of 2). One pin omitted for orientation purposes.

0 0 0 0 0 0 0 0 Viewed from above
0 x 0 0 0 0 0 0
2

Silk screen markings on the motherboard are adjacent to non existent connectors.

To the best of my knowledge, (senility is setting in!), the Model number was X300, at least that was the label on the case front.

I have researched many mboards that have E139761 on them.

Unfortunately the obvious E139761 labelling is used on a small number of old models of made by Intel mboards that are completely different from one another - that isn't enough info by itself.
Many of these mboards were identical to Intel models, the first part of the bios string was the same, the 3 digit manufacturer code was different from Intels's, the bios was modified by or for the the brand name builder, except they possibly didn't have all the optional features installed, and you can use the Intel manuals and other support info. Some were OEM only - made by Intel but Intel didn't market that model, and there are a few models there is support info and manuals for a few OEM manuals on the Intel web site, but for most support is only found on the brand name builders site if at all.

Mboards made by Intel for brand name systems other than Intel that are the same as Intel models always have the Intel model number printed on them, usually in smaller characters near the center of the mboard, but it may be under something such as a cpu heatsink - e.g. if you have a PII cpu in a slot 1 slot computer, it may be an AL440LX - if the mboard has the huge heatsink rather than a smaller heatsink and a cpu fan, the model is under the huge heatsink. Another clue is at least one main chip has ....440LX on it, but AL440LX is not the only possibility that has that.

If that doesn't sound like the one you have, I need to know
- what chipset it has, the first few lines on the main chips
- what type of cpu, and cpu socket
- what slots it has and the numbers of them
- does it have built in AGP ports, if so how many
- onboard video and/or a video slot (AGP)?
.....

"Silk screen markings on the motherboard are adjacent to non existent connectors."

That's common on made by Intel for brand name system builder mboards - not all of the optional features may be on the mboard, and there may be more than one header for front panel connections.

Meanwhile, I'll look up whether the Dell X300 model info, if that's correct, reveals anything.

Oops

- does it have built in USB ports, if so how many

Dell X300 appears to be incorrect - there are Latitude X300 series notebooks, but not X300 anything else on the Dell (Canada) site.
If this is in it's original case see if you can find the actual model number or it's service tag:

http://support.dell.com/support/top...
.....

Dell Dimension L800 CXE has the AL440LX

AL440LX support
http://support.intel.com/support/mo...

AL440LX manual
http://support.intel.com/support/mo...

Other old mboards, some have 440LX:
http://www.intel.com/support/mother...
.....

If you don't have 440LX, I have more possibilities I've already found the info for.

Thanks for the effort you're putting into this - I had no idea it would be so difficult to get data on a Dell board.

The chips. One is marked PC97307-IBU/VUL and 2S9742AKE4. The other is marked Intel PCIset and FW82371AB and F737TB13 and SL23P.There is another, part obscured by the P2 heatsink assembly, marked CY2275APVC-12 and PHI 9738
and CYP 607879. The largest chip is almost completely under the cpu heatsink assembly and so I can't see any of the markings - I don't want to disturb the cpu and heatsink unless absolutely necessary. I can't see AL440LX anywhere.

The CPU is a Pentium 2 but I don't know the type of socket it's mounted in. The processor assembly has a large heatsink affixed to the black plastic CPU case, but there is no fan attached (forced cooling in the original Dell tower case was limited to the fan in the PSU).

The board has 2 ISA slots, 4 PCI slots and one AGP slot.

No on board video.

2 USB 1 sockets, mounted one above the other between the stacked mouse/keyboard sockets and the stacked LPT1 and COM1 sockets

The header for the front panel connection is Silk Screened as J8F2.

STOP PRESS. The wife is convinced that she can see the characters LX at the right hand end of a line of characters, the next line down ends in a 7, then 96 further down, and right at the bottom edge is a line ending with A.

It's almost certainly a AL440LX board. I've looked at the Tech Spec on the Intel site (thanks for the link) and the board I have is a greatly depopulated version (only one COM port, no sound etc. I suppose that's how Dell make their profits). My board also differs from the published data regarding the Front panel header. The documentation shows a 27 pin single in line header but this is not populated on my board, instead I have the 16 pin double row header, which is not shown in the spec! However, now that I have the 27 pin assignations I can buzz through to the double row header.

Thanks again for your help. By the way the Dell model number was XPS D300, my memory again!

No, it's not the AL440LX.
AL440LX doesn't have J8F2.
It's front panel header is J8H2.

This is your mboard:
http://support.dell.com/support/edo...

I'll see what else I can dig up.

Lots of info here - no pinouts found for J8F2.

Manuals (and specs, diagrams, etc.)
Dell™ Dimension™ XPS Dxxx Systems
http://support.dell.com/support/edo...

Dell Dimension XPS Dxxx Systems Reference and Troubleshooting guide (system manual with some case and mboard information):
http://support.dell.com/support/edo...
mboard diagram page 32 of pdf
"Control Panel Connector" - J8F2
No pinouts for that in manual
How to remove/replace the processor pages 97-98 of pdf
Has Yamaha Sound
......

I have come to the conclusion that this mboard is an OEM only version, one that has no Intel model equivalent. In that case custom front panel headers/connectors are sometimes used that are not the same as for the Intel mboard models.

It is common for brand name system builders to not specify the front panel connector pinouts because the original cases often have a one piece female wiring connector from the case that can only go on one way.
e.g. Compaq and HP do the same.

....

Try this:

Front panel pinouts for a few Intel OEM mboards (2 rows 8 pins)
http://www.elhvb.com/mboards/intel/...

(from the 1st Dell picture of the mboard above it looks like J8F2 has 2 rows 8 positions)

or

Front panel pinouts for most Intel OEM mboards (2 rows 9 pins)
http://www.elhvb.com/mboards/intel/...
......

When you get it working, could you please copy down the bios string you see on the first blackscreen while booting and post it here.
e.g.
4A4LL0X0.10A.xxxxxx is AL440LX's bios string for a system with a Dell bios.

I believe all those old Dell Dimensions with the single plug are all the same. I checked one I have and, modifying your above diagram:

0 0 0 0 G E C A
0 X 0 0 H F D B

These are the connections:

Power LED D+ B-
Hard Drive LED C+ A-
Power Switch F H
Reset Switch E G

where the + and - indicate the probable polarity of the LEDs. The positive power LED lead is usually the green wire and the positive HD LED lead is usually the red one.

The remaining pins are not used.

Thanks everyone for your help. I think that I now have sufficient info to get the board up & running. 'Switch on' day won't be for a few weeks yet, other priorities, but I'll post here the results and the BIOS string.

1st link - list - is a puzzle

assuming green is power, yellow is HD Activity, my guesses
Power led 1+,2;
HDD led 3+, 4, polarity?
Reset Sw 5,7 or 7,8
Power Sw 5,6 or 6,8
Speaker? - no standard 4 in a row arrangement - 9+, 11, 13 gnd, 15?
16+, 14, 12 gnd, 10?
Infrared? - not enough pins (standard is 6 in a row, 5 used)
......

Oops - second link was mislabelled where I got it from - it's two rows of 8 too

2nd link - diagram
1+, 3 HD Led
5+, 7 Reset Sw
2+, 4 Power led
6+, 8 Power Sw

DAVEINCAPS:
0 0 0 0 G E C A
0 X 0 0 H F D B

15 13 11 9 7 5 3 1
16 14 12 10 8 6 4 2

These are the connections:

Power LED D+ B- = 2+, 4
Hard Drive LED C+ A- = 1, 3+ (polarity?)
Power Switch F H = 6, 8
Reset Switch E G = 5, 7
No pin at 14 is the same

If an led does not light up, reverse the connections.
....

AL440LX - 27 pin positions in a row
No polarities shown
1,2 Power Sw
3,4 Sleep led
5 pin missing
6,7,8,9,10,11 Infrared +5v, key, IrRX, GND, IrTX, CONIR
12 pin missing
13, 14 pin missing, 15 n.c., 16 HD led
17 pin missing
18, 19 pin missing, 20 Power led
21 pin missing
22,23 Reset Sw
24, 25 missing, 26 n.c., 27 Speaker - GND, key, Peizo_In, Spkr_hdr (+)

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

2nd link - diagram
Speaker?
A standard speaker connector is 4 in a row with wires only on the ends - polarity of a single speaker doesn't matter.
9,11,13,15 ? or
10, 12, 14 missing, 16 ?
Infrared? - not enough pins (standard is 6 in a row, 5 used)

The 16-wire cable connects from the motherboard to a small circuit board that clamps to the front panel. The pins I specified as 'not used' meant there was no function for them on the circuit board. They dead-ended there. Of course it's quite possible the unused motherboard pins have a use but just aren't connected. It does seem odd only 8 out of 16 pins are used. So the remaining pins may be for a speaker, sleep mode LED or other typical motherboard connections.

You mentioned silk screened marking referred to non-existent connectors. The solder points are probably there though. So if you take an ohmmeter and connect between those solder points and the remaining pins you may be able to determine their function.

"The 16-wire cable connects from the motherboard to a small circuit board that clamps to the front panel"

I have one old Dell Optiplex slim Desktop that has the same, only it's 10 wire. Piezo device on the mboard instead of a case speaker connection.

Yeah, I'm working on an Optiplex Gx110 with that same 10-wire connector. I'm hoping all the 16-wire ones are configured the same.

For TubesandWires.

Finally got round to powering up. Power on and reset connections seem OK but power led and hdd led don't seem quite right, they light ok but go out now and then! Must recheck connections.

The boot up bios string is:

4A4LL0X0.10A.0027.P09.9803261356

Thanks for getting back to us and supplying the bios string. So it IS an AL440LX with an OEM front panel header.

"...power led and hdd led don't seem quite right, they light ok but go out now and then!"

The hdd led lights only when the hdd is accessed, of course.
You can use something tiny such as a tiny jeweler's screwdriver or a sturdy sewing needle to bend the female metal wire ends inside the twin female shrouds for the leds so that they grip the pins more tightly.

AL440LX support
http://support.intel.com/support/mo...

AL440LX manual
http://support.intel.com/support/mo...

The Motherboard Specification Update lists errata in the original manual, and what was fixed and what wasn't in later bios versions.
The latter part of the Dell bios string is probably not quite the same, but you can get a general idea of which bios version it is similar to by comparing that to the Intel bios strings.

With the newest Intel updates I seem to recall the mboard will support up to a slot 1 PII 450mhz cpu, which is available quite cheaply on the web these days. There is probably also info on the web as to what slotkets you can use to convert the slot 1 slot to a socket 370 socket, and what cpus can be used with the slotket in this mboard, which may be faster still.
You must move a configuration jumper on the mboard when you want to change the cpu speed in order for the settings for it to show up in the bios Setup - see the manual, pages 26 and 42 of the pdf.

Your OEM version may be missing connectors/pins in places, in addition to the ones for the Intel front I/O header J8H2 that you have already discovered.
If the configuration jumper pins aren't there, you can still short the appropriate solder dots where they should be.
Similarly, some pins may be missing for other things such as some of the input headers for the onboard sound - if the Yamaha chip is there, you can connect to the solder dots if you need to.
You can install inexpensive standard pin headers (spaced at .10" intervals) available at electronic parts places - an inexpensive manual solder sucker will help you remove the solder from the holes so that you can solder in the header in one piece.

Also -

That mboard originally used PC66 SDRam or 66mhz FPM or EDO? ram.
The 440LX chipset is more picky than usual about which DIMM ram you use. I have had some experience with trying several different types of faster modules with this mboard, and my findings probably apply to any mboard with a 440LX chipset.
See the last part of this starting with
"Older computers will often not properly recognize ....."
http://www.lanyoncomputers.com.au/c...

You can get quite fair video performance out of it if you use a decent AGP card such as one of the ATI 128 bit series - e.g. Rage Fury (32mb with TV out), Rage Xpert (16 or 32mb), etc. (32mb is best if you want to use higher resolutions) Rage Fury Pro (32 or 64mb) works well too, but of course you can't use it's 4X AGP on the mboard.
.....

You can flash your bios to an Intel version if you like, but if you do, you have to make sure you flash the boot block portion as well as the rest of the bios. I don't know whether the oddball Intel flash utility iflash does that. I recommend you use Uniflash rather than the Intel flash utility.
If you want more info about how to do that, just ask.
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