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Millyons
04-24-2004, 10:18 PM
Please could someone help me out with soldering onto the mosfet drain, i tried and tried and i just cant get my solder to stick to it, i really need this mod so i can use my new BH5 KHX3000 stick on my mb :)


edit:


Oh ya and I got a 25W soldering iron


And could i mabey use Artic Silver Adhesive to gule it on instead of soldering?

XanderF
04-24-2004, 11:36 PM
In really sticky situations like this, I try to wrap the wire around something - brace it under a piece, something. Put the solder on it to make good electrical contact, then use a big glob of hot glue right over it to hold it in place.

There has got to be a better way, I agree, but this was always my 'getto' solution to those one or two solder points that *just* *won't* *stick*.

Holst
04-25-2004, 01:12 AM
You probably done have enough wattage in your iron to melt the solder on the mosfet.

It may help to put a bit of solder on your iron before you try to solder to the pad.

Be carefull you dont get a dry joint, easily done if you dont have a big enough iron.

I would NEVER recomend using silver adhesive or glue or antyhing with this sort of mod.. recipe for disaster.

You just need a bigger iron for these types of jobs.

enzoR
04-25-2004, 07:09 AM
yup... use something like 40W

Millyons
04-25-2004, 12:39 PM
:( bah, I cant go and buy a new soldering iron right now.

How long do you guys figure would be safe to hold a 25w iron to the mosfet drain without killing the mosfet?

I know i just need to get it hotter but im afraid of holding it to long and overheating the mosfet, I do have a heatsink on it though.

enzoR
04-25-2004, 02:05 PM
maybe 5 seconds... be sure to blow on it afterwards to cool it off.

Hell-Fire
04-25-2004, 10:35 PM
As crazy as this may sound, if you cant get it to stick, put some flux paste on the place you want to solder, then solder away.

Has always worked for me.

I would also do what Holst said, put some solder on the tip, then touch that to the place you want to solder to add little there to help the joint seal. Then cover the wire end thoroughly with solder. Then hold the 2 together and apply the heat.

Karnivore
04-26-2004, 01:23 AM
In addition to the above suggestions, some electronics components have a kind of Zinc coating which doesn't solder easily.
Typically if this is the case increasing the heat will usually do the job.. Alternately if you take a knife, file, or some similar tool , and rough up the surface it sometimes helps make a good joint at more reasonable temperatures...

Millyons
04-26-2004, 08:40 AM
Thanks guys, I tried 100 times on a old mb but no luck so i just gave up and soldered onto the mosfet middle pin.

Millyons
04-26-2004, 11:17 PM
One more question,

Mod is:
psu 3.3 rail ---- coil --- cappacitor ---- vdimm mosfet middle pin
and negative of the capacitor to ground


I used standard psu wire 18 awg (gauge?)

Can i use like a 26awg (fan wire) to the mosfet middle pin instead of 18 gauge, i need to know cause i need more flexible wire than the psu one, i understand there some amps running through there but how can i know what wire thicknes can handle what kind of amerage?

thanks

STEvil
04-27-2004, 12:06 AM
what are you trying to accomplish?

Cap to ground is bad idea.

Millyons
04-27-2004, 08:15 AM
This mod
Already did it works good, just my wires are to stiff and cant place my mod anywhere

http://forums.pcper.com/showthread.php?t=297579

Holst
04-27-2004, 09:20 AM
Originally posted by STEvil
what are you trying to accomplish?

Cap to ground is bad idea.

I think the point of taking the cap to ground is to "reinforce" the ground plane of the board (in the same way that this mod appears to reinforce the 3.3v plane)

So taking the cap to ground seems ok... although I doubt very much if this will gain you anything..

Millyons
04-27-2004, 10:17 AM
That mod works great, i don't know if that cap is needed or not but the mod is awsome,

my vdimm when set to 2.8 with 2 - 512mb sticks dmm mesured idle 2.89v and load 2.78v after i did the mod it is at 2.98v idle and load



what do you guys think of this

http://www.xtremesystems.org/forums/showthread.php?s=&threadid=34240

Ragnarok
04-27-2004, 07:06 PM
that inductor and capacitor in the pic forms a low pass filter...

uwackme
04-28-2004, 07:09 AM
You'll achieve a BETTER stabilization if you just up the 3.3V rail from your powersupply to 3.5-3.6V. Usually there is a pot inside the PSU, or read about 3.3Vrail mods elsewhere here.

Dont bother with any of that coil/cap nonsense. VooDoo electronics.

Reason it's so hard to solder.... the power and ground planes in the PCboard have alot of copper and require ALOT of heat to get to solder melting point. You need a serious soldering iron to do this kind of work.

Millyons
04-28-2004, 08:43 AM
I got a enermax with "PC Ice's" 3.3v mod and the rail is at 3.7, also a adjustable forton with the 3.3 at around 3.6 ish, and i already did the "coil/cap" mod and it works awsome.

But now i just wondering is it smart to find individual slot voltage points on the back of the mb and concet them, since each slot has different oc ability with a same stick of ram.

Millyons
04-28-2004, 05:06 PM
K nm i just mesured individual dimm voltages idle and under-load and they are all the same..........