  We study effects of the heavy top quark ($m_t \approx 180 GeV$) on the scalar
sector of the minimal Standard Model. We construct the effective potential for
the scalar doublet, by first taking into account the leading contributions of
the top quark loops. Minimizing this potential gives us a condition analogous
to the leading-Nc gap equation of the standard ${\bar t}t$-condensation model
(Top-mode standard model). This essentially nonperturbative condition leads to
a low ultraviolet cutoff $\L = O(1 TeV)$ in the case when the bare mass $\mu$
of the scalar doublet in the tree level potential satisfies $\mu^2 = -M^2_0
\leq 0$ and the scalar doublet there is selfinteracting ($\lambda > 0$). We
demand that the scalar selfinteraction behave perturbatively -- in the sense
that its 1-loop contributions influence the effective poten- tial distinctly
less than those of the Yukawa coupling of the heavy top quark. When we
subsequently include the 1-loop contributions of the scalar and the gauge
bosonic sectors in a perturbative manner, the results change numerically, but
the cutoff $\L$ remains $O(1 TeV)$. The resulting Higgs mass $M_H$ is then in
the range 150-250 GeV. Furthermore, the results of the paper survive even in
the case when the square of the bare mass $\mu^2$ is positive, as long as
$\mu^2 \leq O(\lambda v^2)$, where $\lambda/4!$ is the usual bare coupling
parameter of the quartic selfinteraction of the scalars and $v$ is the vacuum
expectation value ($v=246.2 \GeV$, $M^2_H \approx \lambda v^2/3$).
