MSI MS-6368 mainboard freezes before loading OS

[gandhig]

After an abnormal power shutdown of my Pentium 3 computer(stuck with it as i had to postpone my new build), the system hangs after PCI device listing. No messages like updating ESCD or verifying DMI etc. are displayed. POST is normal and i'm able to get into BIOS. Tried all the boot sequence with floppy, cdrom, hdd. It is not even reaching the point where it looks for any media to load the OS. All the 1000uF, 6.3V, G-Luxon caps are slightly bloated. I will post the picture of the mainboard soon. RAM and CPU was tested in another system and found OK. Can it be the BIOS got corrupted or due to bad caps?

[kc8adu]

Re: MSI MS-6368 mainboard freezes before loading OS

start by replaceing all the caps.
this is a very old board now and g-luxon are not fine wine that gets better with time.

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

I have attached some snaps of my mainboard and capacitors taken from mobile phone camera(slightly out of focused). At the soldering side of the mainboard, the traces are running very close to some capacitor mount holes. If i mistakenly place the hot iron on these traces will it be permanently damaged. I'm not much experienced in soldering stuff, but i can practice with a pci modem card. Should i go for a conical tip or chisel tip iron? I'm planning to buy a standard 40W iron like goot and hope that it will suffice. A slight brownish tinge was seen on some 1000uf caps, but i could not differentiate whether it is rust or electrolyte? When i scrapped, it came off easily and could not find any leaky holes. i will post some more clear photos.

[Blargh523]

Re: MSI MS-6368 mainboard freezes before loading OS

I prefer a small chisel tip to a cone. You can use the side of a chisel for tighter spots.

Clearer pics would definitely help.

[momaka]

Re: MSI MS-6368 mainboard freezes before loading OS

At the soldering side of the mainboard, the traces are running very close to some capacitor mount holes. If i mistakenly place the hot iron on these traces will it be permanently damaged.

No, not unless you press a little too much on them. Basically, you can have the iron over them but don't rub it against the board.

Use chisel tip, and go for a 50 or 60W iron. It will make desoldering the caps easier and the risk of damaging the board is actually less (since the iron will heat the joints quicker and you won't have to hold it for too long on the board).

You can use the wiggle/walk method to remove the caps, as seen here:
https://www.badcaps.net/forum/showpo...7&postcount=23

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

Thanks for all your inputs. Unfortunately i had bought the iron before seeing your suggestions. It is a goot kx-40r with a conical tip (could not find a chisel tip here at my place). Can i use 5 core rosin leaded solder with lead-free tip soldering iron?

[t.j.]

Re: MSI MS-6368 mainboard freezes before loading OS

Thanks for all your inputs. Unfortunately i had bought the iron before seeing your suggestions. It is a goot kx-40r with a conical tip (could not find a chisel tip here at my place). Can i use 5 core rosin leaded solder with lead-free tip soldering iron?

yes the leaded has a lower melt point then non leaded! an if not rough with it a conical will work for what ya want it to do!

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

i read that using a lead free solder with a leaded tip iron may ruin the tip. Will the reverse i.e. lead solder used with lead free tip iron ruin the tip too?

[momaka]

Re: MSI MS-6368 mainboard freezes before loading OS

i read that using a lead free solder with a leaded tip iron may ruin the tip. Will the reverse i.e. lead solder used with lead free tip iron ruin the tip too?

I never heard of that before. I don't think you'll ruin your tip, though. I use both leaded and lead-free solder interchangeably on all of my irons. Doesn't make a difference at all, other than the cheap irons have cheaper tips that get eaten faster. But that's unrelated to the solder type. Cheap tip on a cheap unregulated iron = tip gets eaten faster. And even so, a very chip iron tip will still most likely last you for at least 10 motherboards recaps before you have to trim/file it.

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

I was able to remove 14 (1000uf) & 4 (2700uf) caps with a bit of struggle using the wiggle method. Probably damaged some components, don't know for sure. Conical tip worked OK during the component removal. Now the hard part, to clean the holes using desoldering braid. In some cases it worked very well and sometimes it doesn't. There are 03(out of 36) holes remaining to be cleared. Tried 2 or 3 times to add new solder and suck it up using the braid, but doesn't seem to work. Tried to insert a needle also but with not much success. Again will give it a try today.

[larrymoencurly]

Re: MSI MS-6368 mainboard freezes before loading OS

Sometimes the braid works a lot better if you apply flux to it or the board.

[momaka]

Re: MSI MS-6368 mainboard freezes before loading OS

Braid will not work on motherboards with thick ground/power planes no matter how powerful or hot your iron is. I tried it with a professional soldering station set at 450C and still nothing even after keeping the iron on there for a minute (this was on a dead practice board). One thing I got out of it, though, is that if you keep the tip too long, you'll ruin the via.
So braid won't work. (And no, pre-hating the board won't help either - I tried.)

The best and quickest method (IMO) is to partially clear the holes and then wiggle the new caps the same way you wiggled the old caps out.

To clear the holes partially, I use a fairly thick needle. First, apply heat with the iron on the solder side, then push the needle on the opposite side until it starts clearing some of the solder in the hole. You don't need the needle to go all the way through the hole - just a millimeter or so. Then remove iron, let solder cool for a second or two and then pull needle. After this, pre-cut the leads on the new caps so they are just the right length and wiggle them in the same way you took the old caps out.

[mockingbird]

Re: MSI MS-6368 mainboard freezes before loading OS

Braid will work, even on tiny lead holes near ground planes if you use a 60 watt iron and braid that is no thicker than 0.05". I imagine it would be even easier with 0.03" braid. I always try to have some of it on hand for this kind of application. If you want to be safe, don't clear the holes at all, just apply some extra solder on the bottom and then wiggle in the new cap while heating each individual lead hole.

One more thing, when you cut the leads of the replacement capacitor, make sure you use sharp flush cutters, otherwise the dull cutting edge will in effect "crimp" the lead end by flattening it, and it will be too wide to fit into the lead hole. If you use too much force to push it through, you will rip the bottom pad right off.

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

1. Flux is already there in the solder and the braid (goot). Is it still needed to be applied separately?
2. I don't know much about ground or power plane. Only that there are solder and component sides and the mainboard is multi-layered. One thing i don't understand is that out of 04 holes (02 nos. 2700 uf capacitors near cpu), 01 hole got cleared fully without any trouble.
3. Will desoldering pump help? I don't want to spend much by the way.
4. I will try the wiggling in method and get a good cutter for the job.

[momaka]

Re: MSI MS-6368 mainboard freezes before loading OS

1. Flux is not needed, but it can be very helpful sometimes. For example, if you want to just retouch/reheat the joints, you don't have to keep adding new solder to make the iron melt the old solder.

2. Some capacitors holes are placed where the ground/power planes are smaller, so that's why it's easier to clear them. The ones around the CPU are usually the hardest

3. I have not had any success with a desoldering pump or desoldering iron.

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

Heating on solder side and inserting a needle from the opposite side cleared one of the holes. one down, two more to go. Due to other works, i could not devote much time and finish it in one stretch. To me, it has now become more like finishing the mess i have started in the first place by going straight into it without much practice. Still i continue and thanks to all of you guys for guiding me when i got stuck up. This served as a good experience and even if i scrap the board, i should say i won't feel dissatisfied.

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

The remaining two holes could be cleared by the needle method. But the motherboard is almost confirmed to be scrap now. I have attached some close-up snaps of the cleared holes.

[momaka]

Re: MSI MS-6368 mainboard freezes before loading OS

The board looks rough but I don't think it's anywhere near scrap.
Your joints need more heat. Try pre-heating the motherboard a little before soldering on it.

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

It worked !!! It went past the PCI device listing and displayed messages 'updating ESCD' 'verifying DMI' and finally 'disk boot failure' as i had connected only cpu and ram. I was actually shocked more than surprised that the mainboard worked right away after the abuse i had dished out to it. My heartfelt thanks to the forum members especially to momaka. Actually i have another similar mainboard with SiS630 chipset (very poor performance) which i'm using right now. That is the reason i took the trouble to recap this MSI mainboard to gain some performance though i know it won't be much. Will continue with further testing of this board as this is only the first step and hope it holds well together till my new build, say, for a year or so.

[gandhig]

Re: MSI MS-6368 mainboard freezes before loading OS

On hindsight, a chisel tip iron would have saved me a lot of trouble probably. I don't have any specialized tool to preheat the mainboard. I didn't intend to spend much on a soldering station or other tools as i was not very sure that the issue might be in the caps. Now that the job is completed, it feels like a simple job. But definitely not at that time.

Just to understand,

1) Can anybody tell me what the colour(dark and light green) of protective lacquer on the mainboard signifies?

2) In the attached pic, the left pad looks different from the right one. Protective coating is gone and i thought the solder pad also got completely lifted and in another 1 or 2 holes too. That's what i feared most, that the connection between the layers might be broken due to excess heat. Am i not guessing it right? If i'm right, then how it worked???