I have this same server and ran into the same issue. The plugs are custom they looklike ATX P4 connectors but have both 12V/5V. I did research to use the H200 and the proper cables for the T410, but only found one page and they were way too expensive. I ended up replacing the whole box with a custom built.
Here what people on the DELL forum susggest for T410:
For Hot Swap Backplanes:
M400M - Primary HDD Cable PERC H200/H700 Card to B/P(Mini SAS to Mini SAS)
P215M - Secondary HDD Cable PERC H200/H700 Card to B/P(Mini SAS to Mini SAS)
For Cabled:
VKFX8 - Primary HDD Cable with Power PERC H200/H700 Card to HDD*4
ND63T - Secondary HDD Cable with Power PERC H200/H700 Card to HDD*2
Source: http://en.community.dell.com/support-forums/servers/f/906/t/19599252