View Full Version : Who can print a fine PCB for a extended 7950gx2 bridge?
Turok
08-06-2006, 07:56 AM
Hello
I'm trying to find a cheap way to put a pair of high performance 1/2" blocks on my single 7950gx2, but obviously space is a big issue.
I tryed finding people with CNC machines who can make a custom block, but its hard to find someone who can do the job for a cheap price.
I thought the best solution would be to just extend the SLI bridge that connects the card to double the size and I can get the longer standoffs and the screws from a hardware store.
Here are the requirements for the PCB (Printed Circuit Board):
1) It has to be VERY thin. 1mm or less.
The thickness of the circuitry on the original bridge is probably about 1/4mm - 1/2mm thick. Im not sure if it really has to be that thin for performance if it fits, tho :p:
2) It has to be double-sided.
3) The board has to be cut to perfection to fit in between the card.
4) It has to be verry cheap since I'm on a budget. Anything over $10 is overpriced IMO. It uses verry little materials, the design is simple, printing it is obviously pretty automated, and coating it is easy.
Another solution that would work with large and small cooling solutions without requireing another PCB mod is to make two cartriges with only the pins extended (which are about 1mm thick) and spaced a bit on the part outside the socket, and then verry thin cables are welded to its corresponding destination from cartrige to cartrige.
One of my concern with this mod is resistance or a loss of performance.
Will a longer bridge with larger circuitry affect performance vs the original short and skinny circuitry bridge?
Pics of 7950gx2 bridge from Rage3D.com:
*Click to expand*
http://www.rage3d.com/reviews/video/nvidia7950gx2/pics/slilink_sml.jpg (http://www.rage3d.com/reviews/video/nvidia7950gx2/pics/slilink.jpg)
*Click to expand*
http://www.rage3d.com/reviews/video/nvidia7950gx2/pics/slilink2_sml.jpg (http://www.rage3d.com/reviews/video/nvidia7950gx2/pics/slilink2.jpg)
*Click to expand*
http://www.rage3d.com/reviews/video/nvidia7950gx2/pics/slilink3_sml.jpg (http://www.rage3d.com/reviews/video/nvidia7950gx2/pics/slilink3.jpg)
*Click to expand*
http://www.rage3d.com/reviews/video/nvidia7950gx2/pics/slilink4_sml.jpg (http://www.rage3d.com/reviews/video/nvidia7950gx2/pics/slilink4.jpg)
If someone can make a PCB like this, but you need more pictures, I can pull appart my 7950gx2 to give pictures of both sides.
crodan85
08-06-2006, 09:55 AM
I don't think here is the best place to ask as those traces look small <8mils and most home made boards you wont get gold fingering (Tin plating at best) and plus you would need someone to correctly layout the board. If you serious then you could have a go with the layout yourself and then send the layout to a board fab but it will probably cost more then $10. Also from the layout of the traces on the board it looks like it is using LVDS if it is there are even more things that you would have to consider.
I gave it a thought. I'm no expert, but since the PCI express lanes are divided, i think the traces are meant to be the exact lenght they are now. You can lenghten or shorten some of the traces sometimes with little or no effect, but at high speeds of transfer it could lead to instability. I concluded my thoughts with 'it can't be done, it's calculated'. If you have a plexi covered block, try covering it with a sheat of metal, maybe you'll get it fit.
EDIT: AFAIk this isn't just the SLI bridge. The bridge is just the shorter part. No prob in lenghtening it. The prob is in the longer part - the PCIe lanes. There's a chip that divides the lanes in between the GPUs and the lanes for the 'top' GPU travel via that bridge. That will give you the prob. For SLI, all PCIe lanes to the two x16 slots must be the same lenght. I guess it's the same here. Only by ensuring they are the same lenght you can ensure the data arrives at the same time.
I may be wrong, if i am, please correct me. If i'm right, confirm that :>
[XC] leviathan18
08-06-2006, 01:45 PM
its been done there is already selling them but quite expensive.... we want a cheap viable solution to this
But why go through all this hassle? Just make a full metal 'water block' and plug it onto a chiller. Sub zero temps (worse than a phase/LN2 though), but the problem is condensation. For that, you can use this. (http://www.xtremesystems.org/forums/showthread.php?t=107744)
[XC] leviathan18
08-06-2006, 03:35 PM
because i want a portable pc?
crodan85
08-06-2006, 04:39 PM
Has anyone got 7950gx2 that can take high res pics of the card and the extender bridge and i might be able to come up with somthing. But getting single qty boards made up wont be cheap.
Turok
08-06-2006, 05:13 PM
Has anyone got 7950gx2 that can take high res pics of the card and the extender bridge and i might be able to come up with somthing. But getting single qty boards made up wont be cheap.
Ok, Ill open my card and give pics of the bridge with a ruler next to it in milimeters.
If 1 bridge is more expensive because you would be wasting an entire printabble PCB board, then do you think you can make several on the smallest printable board you have and sell bridges to anyone who's interrested ;)
Im sure a few in XS would be interreted or would decide to update to a 7950gx2 because of these bridges :D
Ill take appart my 7950gx2 in a moment.
Ill try to post in a hour with the pics
STEvil
08-06-2006, 05:33 PM
grab some old PCI/AGP cards and saw the edge connector off then solder IDE cables to them.
The one large trace will be for power though so you may want to use a larger wire for that one.
Turok
08-06-2006, 06:10 PM
here are some pics.
Afther takeing several pictures, this is the best I got with my cr@%$y camera :rolleyes:
http://img383.imageshack.us/img383/9376/bridge1yt6.th.jpg (http://img383.imageshack.us/my.php?image=bridge1yt6.jpg)
http://img71.imageshack.us/img71/121/bridge2nu4.th.jpg (http://img71.imageshack.us/my.php?image=bridge2nu4.jpg)
grab some old PCI/AGP cards and saw the edge connector off then solder IDE cables to them.
The one large trace will be for power though so you may want to use a larger wire for that one.
I dont have old cards that I can sacrifice to do that, and so much metal may be a bit of resistance. Even 1mm thick traces on a PCB would be better, IMO.
[XC] leviathan18
08-07-2006, 02:02 AM
pink ruler lol
Turok
08-07-2006, 04:55 AM
pink ruler lol
What can I do :shrug:
I asked my parents for a ruler, and thats what I got :rolleyes:
At least it gets the job done :p:
vudoodoodoo
08-07-2006, 06:10 AM
Ok, Ill open my card and give pics of the bridge with a ruler next to it in milimeters.
If 1 bridge is more expensive because you would be wasting an entire printabble PCB board, then do you think you can make several on the smallest printable board you have and sell bridges to anyone who's interrested ;)
Im sure a few in XS would be interreted or would decide to update to a 7950gx2 because of these bridges :D
Ill take appart my 7950gx2 in a moment.
Ill try to post in a hour with the pics
I'd be interested. I made a thread similar to this one in the watercooling section. I didn't know this thread existed. :(
Turok
08-07-2006, 06:17 AM
I'd be interested. I made a thread similar to this one in the watercooling section. I didn't know this thread existed. :(
Lol, I just noticed that.
http://www.xtremesystems.org/forums/showthread.php?t=110210
Well, the more people get interrested, the better the results :D
Unlike my previous 7950gx2 custom waterblock thread :rolleyes:
http://www.xtremesystems.org/forums/showthread.php?t=104693
crodan85
08-07-2006, 06:22 PM
Can you look on the connector for any text numbers anything that might point me in the way who makes the connector and hopefully some data on it.
Turok
08-07-2006, 06:34 PM
Can you look on the connector for any text numbers anything that might point me in the way who makes the connector and hopefully some data on it.
awww... You tell me this too late :(
I already put the card together yesterday.
What's the slot code for?
crodan85
08-07-2006, 06:49 PM
Well I need the datasheet of the connector so I can find the size , pitch and layout for the gold fingers as I wont be able to guess the size without . Then I can put this into a pcb layout program.
Turok
08-07-2006, 07:04 PM
Well I need the datasheet of the connector so I can find the size , pitch and layout for the gold fingers as I wont be able to guess the size without . Then I can put this into a pcb layout program.
I see...
I wont be able to do it today... sry :(
I will open the card again tomorrow in the morning.
Ill see what I can get for ya.
Turok
08-08-2006, 06:21 AM
Here are 4 pics of the bridge slot:
I checked the sides of the plastic slots,
and there was nothing printed, so I just
took pics of the card around the slot area.
* Inner card - Back:
http://img259.imageshack.us/img259/8546/2gr3.th.jpg (http://img259.imageshack.us/my.php?image=2gr3.jpg)
* Inner card - Front:
http://img209.imageshack.us/img209/3736/1zq6.th.jpg (http://img209.imageshack.us/my.php?image=1zq6.jpg)
* Outer card - Back:
http://img259.imageshack.us/img259/8782/3ox4.th.jpg (http://img259.imageshack.us/my.php?image=3ox4.jpg)
* Outer card - Front:
http://img209.imageshack.us/img209/7940/4dy7.th.jpg (http://img209.imageshack.us/my.php?image=4dy7.jpg)
because i want a portable pc?
Touche. I was thinking about benching :)
Turok
08-08-2006, 11:55 AM
Touche. I was thinking about benching :)
Well, in my case it will be for 24/7 stable over 2x 7900GTX SLi speeds.
Load will be mostly with games. Benchmarking will just be to test for stability.
Making a sub-zero cooling system will be more expensive too, since I alraedy have a WC loop, I just need the blocks and a extension for the 7950gx2.
Turok
08-14-2006, 06:09 PM
What happened crodan85?
You havent reported anything new :confused:
Is anyone else able to help?
Please dont let this thread die... :(
hmmm... for some reason ImageShack replaced my image adress for "* Inner card - Front:" with some other pic of a magazine =/
Ill update it when someone else revives this thread too :P
Slayer2k3
08-23-2006, 06:36 AM
Let me state the obvious first, before I say anything at all hehe.
I am a major n00b when it comes to this area of stuff, but I have an idea, so I'm gonna run with it.
I have taken apart a ton of notebooks, LCDs, projectors, and other various small electronic devices, and in everyone of them, is a similar component.
What if you made a bridge out of the same type of connector used for laptop keyboard connections?
It's extremely thin, flexible, can be traced/plated on both sides, and it's going to be a TON cheaper to produce than a PCB redesign...
I know of a company around here that produces such things, but off the top of my head I can't remember their name. i will be going over in that area later today, so I'll grab some info while I'm out.
SlicerSV
08-23-2006, 08:56 AM
i think most people have decided to just wait for DangerDen's solution...
msimax
08-23-2006, 04:47 PM
or this
http://img183.imageshack.us/img183/4262/gbvls1.jpg
http://img183.imageshack.us/img183/7916/79502nv8.jpg
Turok
08-25-2006, 08:14 PM
@ Slayer2k3
Ive been thinking about a similar solution, but the problem is that you would have to solder it to a PCB board with pins so it holds stable in the bridge slot.
But anyway, cheap flexiple traces could be a good start :)
Let us know what you can get. Take some pics if you can.
@ SlicerSV
Some are just waiting for the DangerDen blocks, because noone wants to bother about a custom bridge extension.
With a longer bridge, you can get cheap standoffs from a hardware store and a pair of Maze4 or MP-1 and you will get a better performance than those expensive and restrictive 7950GX2 solutions
@ msimax
Im already aware of ViperJohn's work, but he sells the bridge alone verry expensive. The custom bridge ONLY = $60 :eek:
For those who didnt know, I made a sticky about the 7950GX2.
Right now my main priority is getting a cheap bridge extension. If someone comes with a good solution, I will be happy to give gredits to you on the guide.
http://www.xtremesystems.org/forums/showthread.php?t=112
It would help a lot if:
1) Someone can make PCB
2) Someone has access to AGP/PCI type pin slots
3) Someone has access to nVidia accessories, like a 7950GX2 bridge, so they can be split in half and extended with soldered cables.
Stigma
08-29-2006, 06:38 AM
I hope this thread goes forward =) The 7950GX2 is a very interresting card, but unless we can space those cards out from eachother a bit to get some real cooling in place, it will be out of the question...
-Stigma
Nanometer
08-30-2006, 07:08 PM
pink ruler lol
ROTF
Nanometer
08-30-2006, 07:11 PM
It really isnt hard to make your own SLI bridge. Just take an old video card or some ram, and cute the gold edge off carefully, solder wires to both ends and there you are. :-D
Actually.. It would be eassier to just make coppies of the sli bridge, and edit it on the computer to allow more space. Then print it out to scale and make a PC board?
Turok
08-31-2006, 03:20 AM
It really isnt hard to make your own SLI bridge. Just take an old video card or some ram, and cute the gold edge off carefully, solder wires to both ends and there you are. :-D
Actually.. It would be eassier to just make coppies of the sli bridge, and edit it on the computer to allow more space. Then print it out to scale and make a PC board?
Yes, I've been thinking about ways to print them myself and sell them to the public at a cheaper price without fancy shipping.
This seems like the easiest way:
http://max8888.orcon.net.nz/pcbs.htm
The only problem is:
Where can I get these materials to print a PCB board :confused:
And what are the safety measures (especially using that acid)?:exclaim:
I dont have spair parts that I can cut off the pins.
Also consider resistance. If you look at the pics from the bridge, the traces are verry thin, so I could lose some stability or performance if I make it longer and use thicker wires.
lawrywild
08-31-2006, 07:13 AM
Dude, thicker wires = less resistance, longer wires = more resistance..
So.. if you can get the right balance, you can equal the resistance on the original traces
plus you can use different material of wires to get the right resistance
Turok
08-31-2006, 01:14 PM
Dude, thicker wires = less resistance, longer wires = more resistance..
So.. if you can get the right balance, you can equal the resistance on the original traces
plus you can use different material of wires to get the right resistance
oops :slap:
But anyway if its too thick you will need more energy, so no need to bash me for that mistake :nono:
The balance has to be between length, material resistance, and trace thickness or cable diameter.
Stigma
09-02-2006, 05:05 PM
oops :slap:
But anyway if its too thick you will need more energy, so no need to bash me for that mistake :nono:
The balance has to be between length, material resistance, and trace thickness or cable diameter.
No, this is not right.
The thicker the pathway is = less resistance = better for carrying a signal.
The longer the pathway is = more resistance = worse for carrying a signal.
So if we can make a bridge that has thicker pathways and is not a heck of a lot longer, then we will get a _better_ signal than a normal SLI bridge.
Just to reitterate: having too thick pathways will NOT "use more energy". In fact, the thicker the material that transfers the electrons is, the less voltage is lost along the way (in other words the signal does not weaken as fast).
So... I see no problem with this.
-Stigma
are those golden connection points a special printed version for the GX2 or just a standard one?
Turok
09-03-2006, 01:58 PM
are those golden connection points a special printed version for the GX2 or just a standard one?
huh:confused:
Do you mean the pictures of the bridge with the ruler?
That's the original bridge and there's not gold on it.
They used regular copper PCB, otherwise the GX2 would be pretty expensive :rolleyes:
Noone has tryed printing one yet, but Im thinking about trying it.
Anyone know where I can get a blank double-sided 1mm thick copper Printable Circuit Board (PCB)?
p0tter
09-05-2006, 11:18 AM
I would buy the one from Viper John, he does great work and its proven. I wouldnt waste time, or money paying someone to incorrectly make it..
If you dropped $500+ on the card already, I wouldnt take a chance.
Nosfer@tu
09-06-2006, 06:09 AM
Me neither.
Time= money and when you finnaly have one you spent more than 10 hours on it.
Holst
09-21-2006, 10:10 AM
I would buy the one from Viper John, he does great work and its proven. I wouldnt waste time, or money paying someone to incorrectly make it..
If you dropped $500+ on the card already, I wouldnt take a chance.
Same here IMO.
I once Tried to make an adaptor that would let me mount an AGP card paralell with the motherboard so it would fit into a very thin case. (resting on PCI slots below)
I Made it out of an old AGP card cut up and a motherboard AGP connector.
It sort of worked but even with the wires all the same and the same length it was still buggy.
These traces may not only be affected by resistance, but also capacitance as well.
Im not saying what your planning wont work (I honestly have no idea) but if there is a commercial solution out there I would buy it personally.
INJViper
09-23-2006, 12:30 AM
I would buy the one from Viper John, he does great work and its proven. I wouldnt waste time, or money paying someone to incorrectly make it..
If you dropped $500+ on the card already, I wouldnt take a chance.
Viper John's work is amazing I would definitly get his.
Why not just buy one of these? http://www.crazypc.com/images/coolers/chip/gx2kit/gx2kitfull.jpghttp://www.crazypc.com/images/coolers/chip/gx2kit/gx2kitexamplefull.jpg
You can get it at http://www.crazypc.com/products/9363GX2.html and it's only a 2 cups at Starbucks.
Kasparz
10-23-2006, 10:21 PM
Because this thread is 1.5 month old, and when he made thread, there would not be available these spacer kits.
It may have started 1.5 months ago, but it's still a live thread and so what if they weren't available then, they are now and it's what he's looking for.
that kit is exactly what is needed. A longer bridge, standoffs, and even a ramsink.
I'd buy it if i had a 7950 :(
natedog420
10-30-2006, 10:11 AM
just a thought. take a piece of pcb thats measured and cut to fit the bridge and lay tape across it then cut out the lanes u need. then take conductive ink and lay it down on the lanes u need then let it dry pull the tape off and u have ur bridge. i dont no how long it would last or how good it would work but its a cheap mans way of doing things lmao.