In this paper it is shown that for the ordinary Dirichlet series, $$\sum _{j=0}^{\infty }\frac{\alpha _{j}}{(j+1)^{s}}$$
∑
j
=
0
∞
α
j
(
j
+
1
)
s
, $$\alpha _{0}=1$$
α
0
=
1
, of a class, say $${\mathcal {P}}$$
P
, that contains in particular the series that define the Riemann zeta and the Dirichlet eta functions, there exists $$\lim _{n\rightarrow \infty }\rho _{n}/n$$
lim
n
→
∞
ρ
n
/
n
, where the $$\rho _{n}$$
ρ
n
’s are the Henry lower bounds of the partial sums of the given Dirichlet series, $$P_{n}(s)=\sum _{j=0}^{n-1}\frac{\alpha _{j}}{(j+1)^{s}}$$
P
n
(
s
)
=
∑
j
=
0
n
-
1
α
j
(
j
+
1
)
s
, $$n>2$$
n
>
2
. Likewise it is given an estimate of the above limit. For the series of $${\mathcal {P}}$$
P
having positive coefficients it is shown the existence of the $$\lim _{n\rightarrow \infty }a_{P_{n}(s)}/n$$
lim
n
→
∞
a
P
n
(
s
)
/
n
, where the $$a_{P_{n}(s)}$$
a
P
n
(
s
)
’s are the lowest bounds of the real parts of the zeros of the partial sums. Furthermore it has been proved that $$\lim _{n\rightarrow \infty }a_{P_{n}(s)}/n=\lim _{n\rightarrow \infty }\rho _{n}/n$$
lim
n
→
∞
a
P
n
(
s
)
/
n
=
lim
n
→
∞
ρ
n
/
n
.