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Reefa_Madness
08-30-2005, 05:34 PM
Hey guys, I need some help...

I purchased a used DFI NF2 Infinity to play with and during transit the aftermarket heatsink/fan, which was attached to the SB with thermal tape, came loose and knocked off a small component.

I found a pic of the same mobo that a member has for sale and I circled the part that fell off. I have the part and it was a clean break of two solder points on the underside.

What is this component and what does it do? Can it be re-installed, for example, if connected by two small wires between the component and the mobo? Any suggestions are appreciated.

I have not attempted to use the MB because I don't want to risk any damage.

Can one of you guys help me identify what it is that I'm dealing with?

Thanks in advance.

jeremywills
08-30-2005, 05:43 PM
oh wow, so thats what got knocked off??? I still dont understand how that happened, Im really hoping you can just resolder that piece on there. Again my apologies.

Jeremy

freecableguy
08-30-2005, 06:06 PM
Thats an oscillator. i.e. reference clock generator

Reefa_Madness
08-30-2005, 06:07 PM
The part lies flat, on an oval "plate" and the solder points are probably legs that are soldered from underneath, however, they broke off flush with the underside so it would appear that the only option would be to either solder new legs to the component and remove the old ones from the PCB and re-install or what would appear to be the easiest which would be to connect it with short wires, like it was some kind of VR.

Again, I am open to suggestions about re-installing, but I am also trying to find out just what it is and how critical is it.

freecableguy
08-30-2005, 06:08 PM
BTW, you would be better to order a new one (find the part number or the clock speed in MHZ on the part top) and get it from DigiKey (http://www.digi-key.com). It will be cheap. You need to first use a soldering iron to remove the leads from the board and the left over solder in the through-holes. Then solder in the new one from the bottom of the board. Pretty easy repair.

-FCG

Reefa_Madness
08-30-2005, 06:09 PM
Thats an oscillator. i.e. reference clock generator

Thanks for the identification...so now...what can I do as far as a fix?

freecableguy
08-30-2005, 06:10 PM
Oh, its an SMT component? Nevermind ordering the new one then. Try to resolder or attach SHORT wires to make it work. Short as possible if you can't solder directly to the board. A little skill and you can make it look stock again. Don't worry about too much heat with that oscillator...it can take quite a bit...it is really just a small crystal in a metal package with some capacitance wrapping.

Reefa_Madness
08-30-2005, 06:14 PM
Thanks again. The short wire approach will have to be the way to go because there simply is no room to solder it flat to the board. Substitute short legs might work also but the wires would be by far the easiest.

Just curious, will this (any) mobo work without it?

i found nemo
08-30-2005, 06:36 PM
the ossilator should read 14.***** on it i forgot, but i could still be wrong

Reefa_Madness
08-30-2005, 07:13 PM
That component has the following across the top: 12.0F4C

The third entry could either be a zero or the letter "O", I can't really tell. A google search earlier revealed no match.

Reefa_Madness
08-31-2005, 02:18 AM
So any thoughts about whether or not the board will work without this component and if it does work, what will be affected?

Thanks in advance for any and all help.

BB mods's
08-31-2005, 11:06 AM
Send her in,ill have u back up in no time bro :)

Reefa_Madness
08-31-2005, 11:22 AM
So is this a case of cutting this crystal loose from behind and replacing it with a new one?

And what does this part do?

I'm not trying to be cheap, but if I can avoid $25 worth of shipping on a board that I paid about $60 for, I certainly might consider trying to fix it myself.

If it was a new $180 mobo, then the reasoning would change, of course. I'm just trying to be practical as to how I go about getting this repaired.

Does anyone know where parts like this can be obtained (again, just what is this part)...DigiKey, DFI directly???

BB mods's
08-31-2005, 11:28 AM
Hey reefa ill locate the part u need and shoot u link to it,..btw i see your from jax...i used to live there for bout 17 year's :)

Reefa_Madness
08-31-2005, 01:03 PM
Thanks man...a link to the part would be very appreciated. Also...any chance that a "repair" with wires or new legs would work?

Hate to sound like a broken record, but can anyone tell me what this part does and whether or not the board can/should be used without it? (side note for you young guys: a record was a circular plate with grooves cut into it which would spin and those grooves could be read by a stylus, producing high fidelity sound. When broken, it would repeat itself over and over. :) sorry guys...I just couldn't help myself)

As for Jax, I moved here in 1979, left for a couple of years in 1997, returning in 1999. I really like this part of Florida...hasn't become a concrete jungle, yet.

freecableguy
08-31-2005, 01:24 PM
It's a reference clock. I.e....for one of the buses to set the speed. It takes that reference speed and multiplies it by a constant to get a speed. 33Mhz for the PCI bus, 66Mhz for the AGP bus, 100Mhz for USB..etc. The board MAY work without it but something might not work...PCI, AGP, USB bus...who knows?

Reefa_Madness
08-31-2005, 02:02 PM
Thanks for that last reply...it helped alot.

At least now I know what area is being impacted by that component. I'm in no hurry with respect to this board so I'll refrain from trying it out until I'm able to fix the part.

Now for that link.... :)

jeremywills
08-31-2005, 03:57 PM
interesting, I was just taking a look at my current board and noticed one near things like the SATA controller, one near the sound chip, one near the temp monitoring sensor etc... its making sense to me what that is, so going off of what I remember what was in that area when I installed that HSF I would suspect it might be the one that was near the SATA controller chip so you might get lucky if thats it and you dont have a need for SATA, I hope thats not the one for the south bridge chip, that would probably be more detrimental, if I had only known I would have removed it before shipping it to you, gosh I feel so bad about it

I hope its an easy enough fix for ya, shoot if your gonna be soldering stuff why not try your hand at vmodding it then just a suggestion

jeremywills
08-31-2005, 04:03 PM
an FYI for ya reefa

interesting read, doesnt help solve the fix but some good material on clock generators and such
http://www.icst.com/Products/appnotes/note04.pdf

Im combing the web now, seeing if I can find anything useful for you to fix this

jeremywills
08-31-2005, 04:30 PM
http://www.mbreview.com/images/reviews/nf2inf/nf2inf-08.jpg

is a pic of the general area, so it might very well be for either, who really knows

Reefa_Madness
08-31-2005, 04:50 PM
interesting, I was just taking a look at my current board and noticed one near things like the SATA controller, one near the sound chip, one near the temp monitoring sensor etc... its making sense to me what that is, so going off of what I remember what was in that area when I installed that HSF I would suspect it might be the one that was near the SATA controller chip so you might get lucky if thats it and you dont have a need for SATA, I hope thats not the one for the south bridge chip, that would probably be more detrimental, if I had only known I would have removed it before shipping it to you, gosh I feel so bad about it

I hope its an easy enough fix for ya, shoot if your gonna be soldering stuff why not try your hand at vmodding it then just a suggestion

That thought had occurred to me so I've started looking for info on the various mods that might be available for the mobo.

And thanks for the link to the info on clock generators.

sluggo
09-04-2005, 07:38 PM
If it only has two pins then it's probably not a "clock generator" but is probably a simple crystal oscillator. Clock generators have nicely squared-off outputs and can drive several inputs. The crystal oscillator's outputs are peaky, but very stable (yours is 12.0MHz), and can't drive anything. They are used as reference timing devices by a clock generator.

They're just a piece of laser-trimmed quartz held between a couple of metal plates. They can be fragile, so if you gave it a good whack there's every possibility that it will not work again. Good news is they're cheap and 12MHz is a common value, available through any mail order place.

The actual value and tolerance is not critical. 12 MHz +/- .1 MHz is probably fine. Don't go spending a lot of money on a 12.0001 MHz part.

sluggo

Reefa_Madness
09-05-2005, 11:36 AM
Thanks for that reply, sluggo.

Would the linked part (10th one down on the left hand side) be what I need?

http://www.goldmine-elec-products.com/products.asp?dept=1037

Reefa_Madness
09-05-2005, 07:09 PM
I sent an email to DFI's USA branch and they responded.

They told me that they didn't have a schematics of the mobo and doubted that DFI Taiwan would either, but sent me their email address just in case I wanted to give them a try anyways.

That was encouraging. :(

jeremywills
09-05-2005, 07:32 PM
shoot, theres this place called Atex electronics here in town, I need to be heading that way tommrow anyhow to run an errand at my savings bank which is right near there, so I'll pop in and see what they have, if so and I can get it for you Ill just mail it your way.

edit, looking at thier webpage would this do?
http://www.shopatex.com/shop/product_info.php?cPath=49_242&products_id=3670

sluggo
09-06-2005, 01:28 AM
Thanks for that reply, sluggo.

Would the linked part (10th one down on the left hand side) be what I need?

http://www.goldmine-elec-products.com/products.asp?dept=1037

Nope. The parts on that page are what's often referred to as hybrid oscillators. They have the crystal and a few other components in that package that you don't want. It's also a 4-pin device and is FAR larger than you have room for.

You want something like this. (http://www.ecsxtal.com/pdf2/CSM-7.PDF)

It's available from Digikey thusly. (http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail?Ref=23784&Row=532920&Site=US)

Just $.73 and prolly $10 for shipping :(

sluggo

Reefa_Madness
09-06-2005, 02:07 AM
Now that does look like the part that I need.

One of the guys had linked me to that site, but I just didn't know just what to search for. Thank you very much for your help.

jeremywills
09-06-2005, 07:25 AM
damn when i clicked the digikey link, its telling me the datasheets expired, please search again, grr sorry i cant print and take it over there to compare

sluggo
09-06-2005, 09:08 AM
Digikey part number is XC741CT-ND

They won't allow hotlinking the datasheet, but it's there if you enter the part number at Digikey's home page (http://www.digikey.com/)

sluggo

Reefa_Madness
09-07-2005, 05:58 PM
Update:

I received an email from Frank Wong of DFI referencing my bronken component and after a brief phone call he offered to send me the needed component.

That certainly made my day and I am most appreciative of his help, as well as the help that I've received from the members here. Wouldn't have known where to start without it.

jumanji969
09-09-2005, 09:18 AM
Good to hear :). Frank Wong is a real good guy.

Reefa_Madness
09-12-2005, 03:22 PM
Kudos to DFI and specifically to Frank Wong!

As promised, the component(s) arrived today via FedEx (they sent me two...just in case I screw up the first install I'll still have one to take to a pro :) ).

jeremywills
09-14-2005, 06:06 AM
Sweet, lemme know how it worked out, if you never can get the board working correctly contact me and Ill gladly reimburse you for all of your troubles