Dell’s gorgeous XPS 13 laptop is now substantially more affordable thanks to a generous discount from Microsoft to celebrate Pi Day. For today only, customers will save 31.4 percent on the entry-level Core i5 model, which reduces its starting price to just $685.31.

That’s significantly less than the $999 price tag that the XPS 13 lineup normally starts at. Unfortunately, this discount is only available on that one model, but Microsoft is also offering 31.4 percent off the Inspiron 13 and the Inspiron 15 notebooks.

You can also save up to $200 on other XPS 13 models, including the two Core i7 models that Microsoft sells. This means the top-tier machine — which has a touchscreen, a Core i7 processor, 16GB of RAM, and 512GB of storage — is now $1,799 down from $1,999.

Microsoft’s discount comes just a couple of days after Dell began selling the XPS 13 with Ubuntu Linux 14.04 pre-installed. But as you might expect, Microsoft is only offering the versions powered by its own Windows 10 operating system.

“Alongside the Pi Day deals, Microsoft has also revealed its new spring sale that starts tomorrow,” reports The Verge. “There’s a $100 discount on some Surface Pro 4 models, and up to 50 percent off a number of PCs and laptops.”

The spring sale discounts will stick around until stocks last, but once again, those Pi Day discounts are available today only, so you’ll need to act fast to catch them.