Dell OptiPlex GX260 and GX270 front pannel pinout

[momaka]

I know these motherboards are pretty old by now, but I decided to post this just in case anyone ends up doing what I did. In my case, I got a Dell GX270 motherboard with bad caps a while back, but no original case. I managed to successfully fit the motherboard (along with its tray) into a standard ATX case. However, when it was time to wire up the front panel, I hit a wall.

Found some diagrams online which helped me get the power, HDD, and power LEDs hooked, though even with those diagrams I still ended up doing some trial-and-error before finally getting the LEDs to work correctly.

Eventually, I got my hands on a semi-dead GX260 PC. Took out the motherboard and front panel connector with accompanying USB/audio and power button boards, then started tracing with my multimeter. The final result:
https://www.badcaps.net/forum/attach...1&d=1406870758

Some notes:
* Pin 5, HDD LED(+), goes to a 200 Ohm resistor on the PCB that holds the power buttons. The other end of that 200 Ohm resistor is what connects to the LED's anode (positive) lead. Negative lead connected to ground.
* There are two (+) pins for the Power LED - pins 23 and 27. On the PCB with the power buttons, the power LED is actually a dual LED (orange and green, I believe). If you have just a single color LED, use pins 23 and 25, or 23 and ground (pin 25 is ground, so it doesn't make a difference where you ground the power LED).
* There is a USB disable(?) circuit on the USB PCB. It involves four N-channel SOT-23 MOSFETs, four 15 KOhm resistors, and a 100 KOhm resistor. I'm actually not sure if it's a disable circuit or what exactly, and neither know if USB ports will work without it. All I can say is that if the USB disable pin (pin 26) goes high, the D(+) and D(-) lines on both USB ports should get pulled to ground. With USB disable pin low, the MOSFETs should be high impedance, and thus the D(+) and D(-) lines should be uninterrupted and communicate with the board. So it probably would be okay if you connected the D(+) and D(-) lines directly to a USB port without this circuit. But I just put it there just in case.
* On the USB board, there are also "Intruder" and "External Speaker" headers. These should be self-explanatory, though (if not, let me know).

Hope this helps someone.

[Agent24]

Re: Dell OptiPlex GX260 and GX270 front pannel pinout

How interesting, I wonder why they have that circuit on the USB

[SteveNielsen]

Re: Dell OptiPlex GX260 and GX270 front pannel pinout

Thanks momaka. I may find this useful if/when I ever get around to transplanting my GX270 into an ATX case. I've been having second thoughts over doing that. The only reason I want to is because my AGP card won't allow the case to close but I'm thinking it would be better to get or make an AGP riser card or cable.

Perhaps that extra USB ckt is for short protection on the front USB ports?

[momaka]

Re: Dell OptiPlex GX260 and GX270 front pannel pinout

Thanks momaka. I may find this useful if/when I ever get around to transplanting my GX270 into an ATX case.

Good to know .
When I found the drawing on my HDD, I remembered that someone was trying to do a GX270 motherboard transplany, but forgot who.

By the way, this is for the desktop tower. I don't know if the SFF has the same pinout or not. But if the connector has the same 34-pin small-pitch layout, it probably is the same. Although, if you are doing a transplant and already have the front panel cables, then might as well transplant that on the new case - easier than finding connectors that plug in the small pitch front panel connector.

Perhaps that extra USB ckt is for short protection on the front USB ports?

It doesn't disable the USB +5V line, just the data lines. Likely not needed for normal operation, though.

Also, I forgot to mention...
the power button board also had silkscreen and holes for an "E-support" switch and LED - neither of which were installed. I don't know what these do - perhaps open Dell's support website if some of their factory software is installed. In any case, it is nothing important, but just wanted to mention it in case anyone was wondering what those "E-sup" switch and LED pins are for.

[Topcat]

Re: Dell OptiPlex GX260 and GX270 front pannel pinout

If anyone wants any GX270 boards, I have tons of them in working condition!! I'd part with them very very cheap....like pay the shipping cheap!

[momaka]

Re: Dell OptiPlex GX260 and GX270 front pannel pinout

^ I thought you still get them in for repair every once in a while. Perhaps not enough to get rid of the working ones?

I myself have started to have an overflowing stash of Pentium 4 boards. Just about every old desktop I find has one. Common as dirt, it seems.

Thus, I am more interested in non-working motherboards (as in, problems other than caps - but not BIOS-related) - at least if it's some interesting rare board, that is.

If it's working, it's boring .

Speaking of which, you have any dead AGP cards?

[Topcat]

Re: Dell OptiPlex GX260 and GX270 front pannel pinout

^
A corporate client paid me to recap these, and then decided they no longer needed them, and told me to 'dispose' of them....lol....corporate waste at its finest.

I have a radeon 8500 that doesnt work...I'm sure there's more, but that's the pick of the litter in the AGP stash.

[momaka]

Re: Dell OptiPlex GX260 and GX270 front pannel pinout

^
A corporate client paid me to recap these, and then decided they no longer needed them, and told me to 'dispose' of them....lol....corporate waste at its finest.

Yeah, I know that all too well.
Few years back, I bought a not-so-shabby sized pack of caps from you for about 30 HP SFF PCs. Recapped like 10 systems, then boss told me the organization is likely going to upgrade most of the computers very soon, so he said the recapping task isn't too important and gave me some other stuff to do.
That said, about half of the 10 computers I recapped did get used, so it wasn't a total waste. And the good thing is, the caps were still sitting at the bottom of the drawer in the desk where I was. Chances are, they are still there. If they are not used, I'll see if he wants to "dispose" of them, like in your case .

I have a radeon 8500 that doesnt work...I'm sure there's more, but that's the pick of the litter in the AGP stash.

If you find like 5 or more dead AGP video cards (preferably at least DX8 and DX9 capable), and you want to clear them out, let me know and name me a price. PCI and PCI-E okay too, of course.