Why leave out the details?

So, incompatible in what way? Please describe your observations.
How big drive it had before, and how big SSD drive you bought for it?
What are you installing on it?

Yes sometimes BIOS can't handle too large drives and hang the system or show smaller drive.

Well the original disk is a IBM Deskstar 12gb, which I wanted to replace due to the noise levels.

The SSD is 128gb in capacity.

When I installed the SSD, the system would act as if there was no drive at all. Non system disk would show up on the screen. The same as when I booted up the system with no disk in at all. I suspected that disk size could be a issue, but surely that would incur a different error ?

I hope to install Windows XP, which is installed on the original disk and works fine.

Have you hooked up the SSD to another system to verify that it actually works?

The other option is to get an IDE to SATA adapter and use a regular SATA SSD in it.

That is what I did with my old Toshiba P-IV laptop.

I did have to disassemble the SSD and trim the SSD case for it to fit with the adapter, but it works fine. You just have to make sure that the SSD itself is small enough to fit.

The other option is to get an IDE to SATA adapter and then a SATA to m.2 adapter and use an m.2 SSD. Probably easier to fit in there, but not quite as cheap as just using an IDE to SATA adapter.

There are quite a lot of different orientation laptop IDE to SATA adapters so you just have to make sure you get one that will work in your laptop. They are pretty cheap at less that $10 a piece.

Yes, do verify that the SSD works on other computers as expected.

But frankly put putting a 128GB drive in place of 12GB drive into an old machine can cause problems.
If the new drive were 32GB there is more chance for it to work, some BIOSes have issues with drives larger than about 32GB.
Some hard drives had jumpers to limit them to about 32GB for these reasons.

If there is no hardware jumper or software that could limit the SSD size to about 30GB then try to find a BIOS upgrade to the PC.

I'd bet a machine that came with a 12GB HDD won't recognize a 128GB one. Of course there are exceptions (or BIOS upgrades) but there's a very good chance that this is the problem.

I was unable to see what type and year of laptop you have. For example I have a Compaq LTE5100 from around '94. It came with a 800MB 2.5" ide disk. I tried various 'modern' disks on it and it seems unable to have them working on DOS at least, because bios detects them as weird much smaller capacities. I think the bios has a limit of about 8 or 10GB in practice. I could have tried Quantum Ontrack Manager and some other work-arounds, but I don't need that much space on so old DOS/Win3.11/Win98 laptop anyway. So I bought a small footprint passive 2.5" pata to CF adapter and started to go through my CF cards instead. They also had a lot of problems with BIOS as expected, but one 4GB card actually worked! I havent' benchmarked it, but haven't ran to any slowdowns and it has worked very well for a year now. For so old laptops you really should rather use a CF or SD to PATA adapter these days rather than an over sized "real" SSD or HDD. What I really miss though is the hard disk sounds, because with also a quiet fan the computer feels or rather sounds totally dead while using it, with less feeling, what is important to me when using a real vintage computer instead of an emulator. So I think I'll some day eBay a still working under 8GB 2.5" pata disk if they don't cost too much.

gothic_hobbit wrote:

Well the original disk is a IBM Deskstar 12gb, which I wanted to replace due to the noise levels. […]
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Well the original disk is a IBM Deskstar 12gb, which I wanted to replace due to the noise levels.

The SSD is 128gb in capacity.

When I installed the SSD, the system would act as if there was no drive at all. Non system disk would show up on the screen. The same as when I booted up the system with no disk in at all. I suspected that disk size could be a issue, but surely that would incur a different error ?

I hope to install Windows XP, which is installed on the original disk and works fine.

Non system disk. I think this sounds like you were trying to boot up on this. You need to get a 98SE DOS bootable disk and format it with sys option. I suggest you use FDISK and partition 1 as FAT16 2GB. Then you can decide how to partition the remainder of the capacity. If you're doing XP then maybe 32GB FAT32 is a good chunk size, and you can make 2 more 32GB FAT32 partitions in case you want to install some other OS or use them for storage. But you need to make the first partition bootable. Don't forget to set the drive as active in Fdisk. Sometimes you have to use FDISK /MBR to force it to be DOS bootable in some cases. Then use Format with sys and then reboot to see if it boots to C:.

If your system is too old it might not be able to use the 128GB SSD so I would also hook this to another system to make sure it works.

I also own an M700 and mine has a 120gb Fujitsu HD in it, which works fine under both 98SE, XP and Windows 2000, so I'm not sure that the capacity is the problem here.

Have you tried checking for an updated BIOS?