Let's denote the speed of the newer personal computer as \(x\) gigahertz.
According to the problem, the operating speed of the older personal computer is \(50\) gigahertz, and this is one-fourth the speed of the newer model. Mathematically, we can represent this relationship as:
\[\frac{1}{4} \times x = 50\]
Now, we solve for \(x\), the speed of the newer personal computer:
\[\frac{1}{4} \times x = 50\]
To isolate \(x\), we multiply both sides of the equation by \(4\):
\[x = 4 \times 50\]
\[x = 200\]
So, the speed of the newer personal computer is \(200\) gigahertz.