I have an early IBM Thinkpad 380ED, and what you should do first is check Lenovo's website for the Configuration Utility that came with your computer (Lenovo has an extensive archive of old IBM computer drivers). There's an option to turn on stretching ("hvexp") and also an option to enable switching between the two settings by pressing Fn+F8 ("f8"). Make sure that, at the very least, "hvexp" is turned on, but I'd recommend both. If you've never used the Configuration Utility before, or just never played around it with at all, I'd also recommend familiarizing yourself with every option, as it can really help you get the most out of using your laptop under DOS. Obviously, if you're using Windows, then you would just change the display settings through there.

Also, I'm not sure if this information would apply in your case, but that's how it's setup through the Thinkpad laptop. YMMV.

EDIT: Is the 9547 the same thing as the Thinkpad 765L? In that case, all this should apply to you, as the Thinkpad Configuration Utility was pretty much used universally by all IBM laptops.