As the Linux patch for the Intel kernel issue is somewhat more mature than the Windows patch which was just pushed out, and because the patch may have more impact on hosting solutions than gaming machines, we turn to Phoronix for test results.  Their testing overview looks at both Intel and AMD, as the PTI patch can be installed on AMD systems and it is not a bad idea to do so.  The results are somewhat encouraging, CPUs with PCID (Process Context ID) such as Sandy Bridge and newer seem to see little effect from the patch, network performance seems unchanged and Xeon's see far less of an effect across the board than desktop machines.  That is not to say there is no impact whatsoever, in synthetic benchmarks which make frequent system calls or depend on optimized access to the kernel they did see slowdowns; thankfully those workloads are not common for enthusiast software.   Expect a lot more results from both Windows and Linux over the coming weeks.

"2018 has been off to a busy start with all the testing around the Linux x86 PTI (Page Table Isolation) patches for this "Intel CPU bug" that potentially dates back to the Pentium days but has yet to be fully disclosed. Here is the latest."

Here are some more Processor articles from around the web:

Processors