If someone does, let me know.... I'll be happy to compensate you (reasonably) in exchange for your burned out board...

Both the NorthBridge & Southbridge can't be continuity tested from the bottom of the board... only way to build the map is to desolder them...

I don't know about you but I'm not about to desolder the chips from my working board. :p

EDIT (2): NVM the previous edit. CN10 has 4 pins (in addition to grounds & VCC) that connects to LAD0 - LAD3 (LBC Bus) on the IT8705F SuperIO Chip. Not sure what they do exactly because I don't yet understand what I've read/skimmed about the LBC Bus.

I've Tracked 4 Pins of CN10 to the LAD0-LAD4 (LBC Bus) of the IT8705 SuperIO Chip and updated previous posts to reflect this info.

I'm looking for a pinout of the 761GX NorthBridge. While it is BGA there are some pins I can test from the back of the board. If we find just one pin I can test that is related to VGA we'll be alot further along.

Cheers

Bit of an update:

Having trouble tracking down an inexpensive oscilloscope to buy or borrow... So I can't test to find the Horizontal & Vertical Syncs (or anything else with a clock to it on the hopefully-present-somewhere vga pins) until I do.

Similarly SIS doesn't seem to be forthcoming with the pinouts for their chipsets... I'll try shooting emails to sis distributors since "developer support" @ SIS isn't coming through with the info.... but I won't hold my breath

Any support anyone else can offer would be greatly appreciated.

another update... (and another self reply)

I made some progress today. I think I've found the Red, Green & Blue Pins.

What I did to find them: Loaded MSDos on a sata drive complete with a config.sys menu consisting of 4 submenus with appropriate background colors (red,green,blue,black) and basically toggled through the colors while measuring the voltages on CN2 pins.

When on a colored menu the pin corresponding to that color should spike compared to baseline (black) and they did.

And finally, I got in contact with the electronics lab manager at my old university and I'll be able to go in and get some oscilloscope time to find the Hsync & Vsync and hopefully the other (less critical) vga pins.

So its only a matter of time folks.

yet another self reply (am I really the only one interested?)

Back from a brief visit to the lab... Found the Vertical & Horizontal Sync. I'm still trying to figure out the rest.

At the 'no boot device found' screen Vertical Sync was ~42.5kHz. Horizontal Sync was ~62.5Hz.

So that's enough to get a picture to display but I need to track down the I2C Sync & Data pins round out the connections to a 15pin VGA connector (nvm the other ~11 pins on CN2).

I'm trying to source a 2mm 26pos crimp connector for CN2. It seems that Locally, metric components aren't stocked. So unless I get lucky it would mean a minimum order of probably 100-1000 connectors to 'do it right'.

No, you are NOT the only one interested...!!

_________________
....JBick

EX475, 2 GB, LE-1640
PC1: Vista-->W7 Ultimate/32, (D-Drive RAID-5 Array)
PC2: Lenovo Laptop, Win XP Home SP3
2xLinksys WRT54G v1.1 and 2xNetGear GS105 Gbit switch

You work it out and I would be interested in buying a cable from you.

_________________
My thoughts are just that, my beliefs and opinions and in no way are supported by HP or anyone else. They are subject to change, as I learn more.

Dunno... I'm much more interested in figuring it out and then posting how to DIY... the whole building/selling/mailing for others thing just doesn't appeal. (sorry). If I find a source for small numbers of the connectors I'll be sure to share though.

The VGA plug I'll use I got from an XFX low profile kit... just need to get the connector for the board side of things.

I'm watching this thread. I expect it to be quite popular when you pull this off.

While I bought this in part because I would not need a keyboard mouse or monitor I find that it needs a bit of tweaking which I feel is better done while you can see what you are doing instead of flying blind.

IMHO HP needs to do some work to set this up the way a server should be before it is ready to be 100% headless.

I wonder as well especially with fooling around with the motherboard on top of a rug or carpeting. Static kills electronic components.

_________________
Richard

My gadget blog: http://www.gadgetinsane.com

Funny you should say that... I did alot of this lying half on a carpeted floor, half on one of those plastic chairmats...

Of course it helped that the unit was plugged in most of the time and i was 'touching ground' at least every minute...

hehe

This is what I was hoping someone with more time and experience would be able to produce.

Thanks!!!

I'm interested!! I always wondered how you technical guys get things figured out like this. Thanks for posting play by play findings!! I will be following this thread like mad, if not to make a cable, but just to learn more about circuitry!!

_________________
Sean
"I do not like the cone of shame."
Boom Boom Room

For the sake of connecting a VGA cable - which you have already shown with your findings to be able to do.

take a look at http://www.kroptech.com/kvm/blackbox.html - site for KVM switch cable making.

The 5V pins are for the PS2 plugs - no voltages needed for the Video cable since it's just red, green, blue, hsync, vsync and all the rest are grounds - which you have already identified. So getting video output from this should be straight forward.

Now finding out which pin is for the mouse clock and data and which is for the keyboard clock and data will be the difficult part. Not sure what the expected throughput signals for that is.

Notice for the sake of the KVM example in the link above - he says it doesn't matter which of the grounds you use for which purpose. Hope this helps.

Yeah after having identified all the pins I need I'm not too stressed about demonstrating that it works... so I slowed down a bit... I finally found the connector & crimps I need (in reasonable quantities) to make the connection from digikey -- my order is in the mail; hopefully arrives next week. All I've been doing since is trying to hash out where I'm going to 'install' the VGA connector. I'm thinking I might try to cut a hole in the chassis where the Kensington security hole is. Either that or feed it to the front of the case and poke a hole there.

I'm also not too stressed about not finding the PS2 ports because I know USB works -- though I still wonder what those LBC pins on CN10 could be used for.

Really to further identify the rest of the pins I (think I) would need access to a logic analyzer. Most of these pins appear to be idle unless something is actually connected and communicating.