YU562 Conroe Dual Core E2140, 1.6G, 1MB, 800FSB, M0
XT482 Conroe Dual Core E2140, 1.6G, 1MB, 800FSB, L2
XT481 Conroe Dual Core E2160, 1.8G, 1MB, 800FSB, L2
YU563 Conroe Dual Core E2160, 1.8G, 1MB, 800FSB, M0
RX391 Conroe Dual Core E2180, 2.0G, 1MB, 800FSB, M0
HU587 Conroe Dual Core E4300, 1.8G, 2MB, 800FSB, L2
DX483 Conroe Dual Core E4400, 2.00G, 2MB, 800FSB, L2
RX522 Conroe Dual Core E4400, 2.00G, 2MB, 800FSB, M0
MP159 Conroe Dual Core E4500, 2.20G, 2MB, 800FSB, M0
CY593 Conroe Dual Core E4600, 2.4G, 2MB, 800FSB, M0
Y933C Conroe Dual Core E4700, 2.6G, 2MB, 800FSB, G0
DX485 Conroe Dual Core E6320, 1.86G, 4MB, 1066FSB, B2
DX484 Conroe Dual Core E6420, 2.13G, 4MB, 1066FSB, B2
MP160 Conroe Dual Core E6550, 2.33G, 4MB, 1333FSB
KU345 Conroe Dual Core E6600, 2.4G, 4MB, 1066FSB, B2
PN416 Conroe Dual Core E6700, 2.66G, 4MB, 1066FSB, B2
MP162 Conroe Dual Core E6750, 2.66G, 4MB, 1333FSB, G0
MP628 Conroe Dual Core E6850, 3.0G, 4MB, 1333FSB, G0

Y442H Wolfdale Dual Core E7300, 2.66G, 3MB, 65W,M0
Y932C Wolfdale Dual Core E8200, 2.66G, 6MB, 1333FSB, 65W, C0
K905F Wolfdale Dual Core E8300, 2.83G, 6MB, 1333FSB, 65W, C0
H399J Wolfdale Dual Core E8400, 3.00G, 6MB, 1333FSB, 65W, E0
Y935C Wolfdale Dual Core E8400, 3.0G, 6MB, 1333FSB, 65W, C0
Y934C Wolfdale Dual Core E8500, 3.16G, 6MB, 1333FSB, 65W, C0
D923J Wolfdale Dual Core E8500, 3.16G, 6MB, 1333FSB, 65W, E0

Thank you for the reply, I have chosen the E7600, not on your list, but hope all runs well!

Regards,

Rob.

you may need a bios update, you may want to check.

YU562 Conroe Dual Core E2140, 1.6G, 1MB, 800FSB, M0 XT482 Conroe Dual Core E2140, 1.6G, 1MB, 800FSB, L2 XT481 Conroe Dual Core E2160, 1.8G, 1MB, 800FSB, L2 YU563 Conroe Dual Core E2160, 1.8G, 1MB, 800FSB, M0 RX391 Conroe Dual Core E2180, 2.0G, 1MB, 800FSB, M0 HU587 Conroe Dual Core E4300, 1.8G, 2MB, 800FSB, L2 DX483 Conroe Dual Core E4400, 2.00G, 2MB, 800FSB, L2 RX522 Conroe Dual Core E4400, 2.00G, 2MB, 800FSB, M0 MP159 Conroe Dual Core E4500, 2.20G, 2MB, 800FSB, M0 CY593 Conroe Dual Core E4600, 2.4G, 2MB, 800FSB, M0 Y933C Conroe Dual Core E4700, 2.6G, 2MB, 800FSB, G0 DX485 Conroe Dual Core E6320, 1.86G, 4MB, 1066FSB, B2 DX484 Conroe Dual Core E6420, 2.13G, 4MB, 1066FSB, B2 MP160 Conroe Dual Core E6550, 2.33G, 4MB, 1333FSB KU345 Conroe Dual Core E6600, 2.4G, 4MB, 1066FSB, B2 PN416 Conroe Dual Core E6700, 2.66G, 4MB, 1066FSB, B2 MP162 Conroe Dual Core E6750, 2.66G, 4MB, 1333FSB, G0 MP628 Conroe Dual Core E6850, 3.0G, 4MB, 1333FSB, G0 Y442H Wolfdale Dual Core E7300, 2.66G, 3MB, 65W,M0 Y932C Wolfdale Dual Core E8200, 2.66G, 6MB, 1333FSB, 65W, C0 K905F Wolfdale Dual Core E8300, 2.83G, 6MB, 1333FSB, 65W, C0 H399J Wolfdale Dual Core E8400, 3.00G, 6MB, 1333FSB, 65W, E0 Y935C Wolfdale Dual Core E8400, 3.0G, 6MB, 1333FSB, 65W, C0 Y934C Wolfdale Dual Core E8500, 3.16G, 6MB, 1333FSB, 65W, C0 D923J Wolfdale Dual Core E8500, 3.16G, 6MB, 1333FSB, 65W, E0

The list Chris posted is probably the list of processors Dell sells/sold on this system at one point or another. This doesn't mean that others won't work, but these are pretty much guaranteed to work.

Hey Chris, I heard that the new BIOS (Version 1.0.16) will support two Intel Core 2 Quad processors.  The Q9550 and another one.  I was wondering if you could confirm this (I'm most interested in the Q9550, but a list of all the newly supported processors would be greatly appreciated).