The Spectre flaw continues to create problems for Microsoft
It turns out that the original patch can cause a “higher than expected number of reboots and other unpredictable behaviors”.
Intel is also struggling with stable patches to updated microcode after halting the rollout of updated patches on Jan 22.
There is the Inspectre tool from GRC.com that you can find a link to on the benaylett.com website which will help you to determine if you are potentially affected by the flaw.
There is also the latest bulletin from Microsoft for those that have already updated their systems to address the previous Spectre patch.