\begin{table}[htb] %[htbp]
\begin{threeparttable}
\caption{\label{tbl:cacheconf} Suggested cache settings for ALU-based reconstruction kernel}
\centering
\noindent
%\resizebox{\columnwidth}{!}{\begin{tabular}{} ... \end{\tabular}}
\begin{tabularx}{\columnwidth}{ | X  c | c  c  c  c | }
\hline
         &        &  \multicolumn{4}{c|}{Caches} \\
GPU      & $n_v$  & $\vfloat{d}$ & $h_m/h_x$ & $c_s$ & $s_p$ \\
\hline
\multirow{2}{*}{Fermi} 
& 1, 2      &  Adv.     & $h_x$ & $c_s$ & - \\
& 4         &  Adv.     & $h_m$ & $c_s$ & - \\
\hline
\multirow{2}{*}{Kepler, Maxwell, Pascal} 
& 1         &  Adv.     & $h_m$ & $c_s$ & - \\
& 2, 4      &  Std.     & $h_m$ & -     & - \\
\hline
\multirow{2}{*}{VLIW} 
& 1         &  Adv.     & $h_m$ & -     & 256 \\
& 2, 4      &  Std.     & $h_m$ & -     & 256 \\
\hline
\multirow{2}{*}{GCN} 
& 1         &  Adv.     & $h_x$ & -     & 256 \\
& 2, 4      &  Std.     & $h_x$ & -     & 256 \\
\hline
\multirow{2}{*}{GCN2} 
& 1         &  Adv.     & $h_m$ & -     & - \\
& 2, 4      &  Std.     & $h_m$ & -     & - \\
\hline
\end{tabularx}
\end{threeparttable}
\end{table}  
