About to mess with a perfectly good $300 motherboard...

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xonik

[H]F Junkie
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Yes, that's right, I have a motherboard meant for embedded applications. It has a standard 184-pin DIMM socket which I'd like to replace with an angled DIMM socket for some additional clearance. Thank God/Allah/Buddha that it's a through-hole PCB mount socket, and I found a suitable replacement.

Now this socket will handle PC3200 RAM. Are there any factors I may not have considered with regards to replacing this socket? It's a through-hole design, and I've done surface mount work before. I think I am capable of doing this, but am I ignoring any important factors?
 
Desoldering motherboard connections is not something to be taken lightly. Just the other day I was trying to desolder the sound/joystick ports to use somewhere else. Even with solder wick, I wasn't able to get enough solder off the joints to loosen the ports. I don't know if they use a different sort of solder on motherboards, but I couldn't get the solder out. I ended up just dremeling the joystick port off (I didn't need the sound ports).
 
You are going to HATE removing that socket, let me assure you... see if you can get your hands on a desoldering gun if you attempt to try this.
 
I got a Hakko 936 grounded iron and some solder wick. Maybe my university has some desoldering equipment. Barring that, any tips on making my life easier, besides abandoning this tedious project?
 
My suggestion is, get a trash motherboard first and try unsoldering a PCI slot from it, pin by pin. See what you think; after you do this, you might think twice about doing it. Removing anything with a lot of pins is hard - motherboards tend to be made on thick PCB's so getting the holes clear on the component side of them is *very* difficult.

Even if you get all but 3 holes clean, the socket will still be stuck to the board. *NEVER* use any force to remove a stuck component like this - there's always the chance that you'll pull the socket off and take a trace with it. You want all holes clean and the socket to practically fall out of the board.

If you can get a desoldering gun (a soldering gun with a hollow tip and a vacuum pump) at your univeristy, then definitely take advantage of it. At my work, we've got the handheld gun as well as a SMT station with a vacuum wand that works just as well.
 
Thanks for the information. Yeah, I got some spare motherboards to mess around with; I'll give them a shot first.

Are there any special things to consider when soldering the new one in? I am proficient at through-hole soldering and have done many TSOP surface mount jobs before. With a complex motherboard such as mine, do I need to I need to pay special attention to grounding or anything else? I'm using a grounded tip at least.
 
xonik said:
Thanks for the information. Yeah, I got some spare motherboards to mess around with; I'll give them a shot first.

Are there any special things to consider when soldering the new one in? I am proficient at through-hole soldering and have done many TSOP surface mount jobs before. With a complex motherboard such as mine, do I need to I need to pay special attention to grounding or anything else? I'm using a grounded tip at least.
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just because it needs to be said...

ground your self... (grounding the gun dont mean squat if you fry it by picking it up wrong(this info more for other peeps that may not know so well))

be shure the holes are absolutly clean and test fit the ram socket it should fall in. if there are other ic componets near by i would try and figure out a way to get heatsinks on them if they are connected by trace, i would say figure out someway to mask off the board around the traces, just incase you slip with the iron, so you dont damage a trace... i was thinking masking tape but i think that might be more hassle than its worth..perhaps a peice of oaktag cut to just the right size ...dunno... (heat + masking tape = big mess not to mention it is still paper and if it gets to hot it may catch fire... )

becarefull to not over heat the traces... i have had them lift off in the past... and about the only other thing i can think of is make shure you pay attention to the keyway... installing it backwards will be a whole new mess... ;) (i beleave the pins are stagered so this is next to impossible... but.. haveing seen people try and install ram in pci slots .. i dont put any thing past any one any more... )

any way... post pics of the befor and after if you get it to work... and a fulll rundown of tools and materials would be nice too...
 
Good stuff to know. Yes, the DIMM slot is on its way and I'll post before and after pictures.
 
the problem you are going to run into (no matter how you do it unless you have some specialized equipment) with removing the slot is you can't remove the pins you desolder, so the solder will reharden, and it will get stuck. due to the proximity of the pins and the size of the holes, one of the vacuum things on a desoldering gun will probably not be able to get all the solder out. you will also have to have a very steady hand to get just the dimm pins heated.

when putting another dimm slot in, you're going to have trouble resoldering the slot, because you need to put 184 VERY small dabs of solder on the board, and not have ANY touching or the motherboard will be fried when you turn it on.

still, this could be cool (and lead to a whole string of people replacing motherboard components) if it works.

as stresstest said, GL you're gonna need it. but don't let me discourage you;) i say go for it as long as you understand the risk involved and are willing to accept it if it breaks.

 
whew all this for a sideways ram slot? I hope it prevails for ya. I added this to my bookmarks so i can keep track of how it goes. Good luck to ya
 
Wow, you guys don't seem too confident in my abilities. Anyways, I'll keep you all posted as I go.
 
xonik said:
Wow, you guys don't seem too confident in my abilities. Anyways, I'll keep you all posted as I go.
Click to expand...
They're just trying not to raise expectations ;)

What you're attempting isn't that difficult, though. A fine-tipped soldering iron, a steady hand, and the right tools to desolder those tiny pins should be enough.

Just don't breath in those fumes =/
 
Oh, sorry to disappoint...I'm not going through with this, at least in my current plans. I've decided to make a radical change in my project that will leave the DIMM slot area fairly clear of obstructions. Therefore, I will hold off on the DIMM slot switchout for now, which is good in that it will speed up the construction process, but bad in that I was kind of relishing the challenge.
 
*snifs the air... * smells like kfc in here... :D

oh well i was looking foward to seeing weather or not you could acctually pull it off or not.. i know i could get the ram ram slot out... but getting the new one in would be the tought part for me... oh well... keep us up dated if you decide to do it any way...

thore
 
aww, well good luck with the rest of your product, this decision wont haunt you for the rest of your life. :D, jk. ;)
 
Hello,
Just a heads up. To remove surface mount components, row's of pins, etc. try using chipquick removal kits. Each kit has a special removal alloy that has a low melting temperature so that you can heat rows of pins and remove them while there still hot.The alloy maintains a molten state long enough to remove chip/card etc...
 
Damn, that's pretty cool, but have you seen any versions that cover through-hole applications? My DIMM slot uses through-hole mounting, which is convenient for soldering but a bitch for desoldering.
 
Even that chipquick stuff is not gonna help.
You will either need a custom tip for your solder station or you will be better off just cutting what you can of the old dim socket out and reducing it to individual pins cause pulling on the socket when you are heating it is gonna pull traces off the board. You just can't maintain enough heat in all of the pins to have the socket pull right off the board.
Been there done that, won't even try it agin. One ruined board was enough. :p :p
 
Well my current plans still don't require me to do this modification. The Chipquik piqued my interest, that's all.
 
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