Flat-pin sockets are better because Dallas chips have flat pins. That's (not only) my opinion.

However, Dallas replacements such as the nwx287 from Scorp (Necroware) use round pins.

Well, this begs another question. Let's say I get the flat pin socket and my battery mod fails. Will that round pin replacement fit in the socket?

Yes, and vice versa. But the best contact will be when they are matched.

Thanks, I will order the flat pin one then.

If you are out of practice with your soldering skills, I would suggest doing the battery mod with the chip in place. Then if that goes wrong somehow, you could try soldering.

2¢

nickles rust wrote on 2025-07-25, 13:17:

If you are out of practice with your soldering skills, I would suggest doing the battery mod with the chip in place. Then if that goes wrong somehow, you could try soldering.

Given its location, feels like a doomed mission...

Going from memory, it looks like they left you room on the side with the battery pins. There are pictures and videos about doing this. A few minutes with a dremel and soldering iron, done. Also, if you warm up the lid a bit the plastic cover and potting compound come off pretty easy.

At least I think this would be easier than un-soldering the chip. Good luck!

Well, here is an example, and the guy miraculously has a ton of room where I have the ISA slot: https://www.youtube.com/watch?v=QOoOZzg3M6A
This looks absolutely brutal to me. You think this is easier/safer than going in with a wick on the other side?

Well, what I initially thought was going somewhat OK seems like a disaster... And the chip won't budge. I am done here and off to ebay for a new motherboard, right?

Why is it a disaster? I think you are almost done. At this stage I usually cut a thin solderwick to a pointy tip and soak it in flux. Then put the wick into the hole beside the legs. This helps to clean up the job. Even if one or two legs are still soldered in the chip wont move. Patience is key here.
Another thing to try at this stage is to take some tweezers and gently wiggle the individual legs. You will probably see that some are already loose and some still fix.

Aui wrote on 2025-07-30, 03:45:

Why is it a disaster? I think you are almost done. At this stage I usually cut a thin solderwick to a pointy tip and soak it in flux. Then put the wick into the hole beside the legs. This helps to clean up the job. Even if one or two legs are still soldered in the chip wont move. Patience is key here.
Another thing to try at this stage is to take some tweezers and gently wiggle the individual legs. You will probably see that some are already loose and some still fix.

Bottom row, 4th from the left, I think I broke a trace there despite being as careful as I could... Let me actually try your suggestions just to see how much damage I've done.

Aui wrote on 2025-07-30, 03:45:

Another thing to try at this stage is to take some tweezers and gently wiggle the individual legs. You will probably see that some are already loose and some still fix.

And if you found fixed pins, there are two ways you can approach it, and you should be aware of both. First, you can re-heat the pin with the iron until it can be wiggled, and then you keep wiggling it while it cools down. This will effectively prevent the pin to get re-soldered while cooling down. Secondly, even if there is no solder at the solder side any more, some solder may be still be in the hole near the other side of the board. Re-solder the pin with fresh solder, than heat it for 5 to 10 seconds with the iron before removing the solder again. The idea is that fresh solder with flux flows better, and performing this procedure mixes the old residual solder with flux-rich new solder, and allows the wicking action to reach the remaining solder.

I recommend trying these two approaches in order. If wiggling during cooldown loosens the pin, it's fine. If not, reflowing and re-wicking is likely going to help, but it obviously is more difficult.

While it will look ugly, you can certainly fix the possibly broken trace with a bodge wire.

I think the most problematic one is that 4th bottom pin from the left. I actually think all of them are loose except that one -- and it is not trapped due to being soldered. It doesn't seem to move when hot, feels seized in the bent pad.

This is the current state of affairs, not much movement from the chip. I actually reflowed and rewicked that pin, followed by some solder pump, but I don't think it's any better.

Using a hot air station or even a heat gun could help here.

PCB is multi-layered and contains large areas of ground and power that act as heat sinks.

If it's only that specific pin and you have any patience left, don't focus on it any more. Make sure all others are free and can move, then as the last step heat the stubborn pin while pulling the chip out. You'll be left with a blocked hole, but it's much easier to clean without the chip in place.

zyga64 wrote on 2025-07-30, 08:07:

PCB is multi-layered and contains large areas of ground and power that act as heat sinks.

I figured as much, but I don't own a heat gun and I think at this point I'd like to limit the investment into things I will be unlikely to use ever again...

konc wrote on 2025-07-30, 08:26:

If it's only that specific pin and you have any patience left, don't focus on it any more. Make sure all others are free and can move, then as the last step heat the stubborn pin while pulling the chip out. You'll be left with a blocked hole, but it's much easier to clean without the chip in place.

I tried exactly this, but sadly I think the top leftmost one is also stuck, just not as badly. Every other pin is able to move, I'm not really sure this is a great indicator of the pin ready to actually come out... I think it only is when you definitely know what you're doing, which may not be my case. 😀

Sorry for butting in. WHY don't you just break the chip with nippers/pliers and then desolder the pins one by one?

Dallas DS1287 DS12887 RTC Replacement nwX287 Real Time Clock Module Battery Kit
https://www.ebay.com/itm/276981098778
https://www.ebay.com/itm/134217827379