I use both in my system, as well as ssd, so maybe I can help you out.

sata to ide adapters will require no f6 drivers when installing, but they are limited by the speed of the onboard controller. If you have ATA33 or ATA66, it can definitely be felt. Your i845 should have ATA100, so its not too bad. The adapters are usually cheap, too.

pci sata controllers will need drivers when installing the OS. They can be SATA300 or SATA150, but they are limited by the PCI bus, so theoretically they will max out at around ATA133 speeds: it really makes no difference which you use unless your motherboard has a PCI-X slot and your adapter is PCI-X. I prefer adaptec or promise chips, they have a bios though and depending on your motherboard you may have trouble booting with them.

Finally, if you plan on installing old windows versions with no official ssd support, I would keep a linux live cd or usb drive handy: you can boot into it and manually run trim every now and then to keep the drive healthy.

Personally I prefer the PCI sata controller, I think the only problem with it is the f6 drivers. If you have both a PCI sata controller and a sata to ide adapter, you can just use the latter to install windows, boot and install the drivers for your PCI sata controller, and then plug the drive into the PCI sata controller for a boost in speed and to avoid dealing with floppy drives.

If you have a Promise S150 based controller you don't need to install F6 drivers... at least not for Windows 98SE.

Also, some/most SSDs have Trim/garbage collection built in from what I could find so you don't even have to worry about running Trim manually. Pretty much all of the newer drives should have it built in.

there are also some SSDs with IDE interface. Transcend for example makes them. They usually but not always are industrial type equipment which means they are a bit pricey but also likely a bit more robust. I have seen them with up to 480GB.

Instead of a 'real' SSD, you could also use SD-cards or Compact Flash cards.
Something like this: https://www.newegg.com/Product/Product.aspx?I … C2386-_-Product
Or this: https://www.newegg.com/Product/Product.aspx?I … 8-002-_-Product
Will just connect up to your IDE controller, and you insert an SD or Compact Flash card as your 'SSD'.
You get the usual advantages of an SSD: large storage, virtually no seek time, no moving parts. But you can also easily remove the SD/Compact Flash card and mount it on a modern system to transfer data.
And it's probably much easier to get going in an old system than a SATA drive.

Sure, performance won't be quite as good as an SSD on paper. But in practice they're much faster than the harddisks you would have in those systems back in the day, and they are probably bottlenecked by the rest of the system anyway.

Is it convenient to run, say, Windows 7 on a large CF card? Any drawbacks here?

bristlehog wrote:

Is it convenient to run, say, Windows 7 on a large CF card? Any drawbacks here?

I haven't tried yet. I'd like to know the same. Is the fixed-media bit still a deal breaker for Win NT OSes ?
If so, can any of the modern SD card to IDE converters mask this bit, so everything appears as "fixed" to Windows ?

bristlehog wrote:

Is it convenient to run, say, Windows 7 on a large CF card? Any drawbacks here?

Yes, CF is dog slow compared to a modern SSD, not worth the bother on anything more modern than Win98 maybe. There's also the issue of wear leveling that _is_ or more commonly _is not_ implemented on CF. SD is worse even.

Just get a cheap and reliable SSD (even secondhand MLC ones), slap an IDE-SATA adapter on it and you're good to go.