Dell XPS 410 Processor Upgrade

XPS410/9200 supports 65nm processors
Core 2 Quad Q6700, is compatible.   1066 MHz FSB   LGA775

The XPS 420/9200 only supports 65nm processors.

Processors that have a 45nm, are not supported.

It is recommended to update the BIOS before a CPU upgrade.

Check that you have BIOS version, 2.5.1, or higher installed.

http://ark.intel.com/products/30790/Intel-Core2-Quad-Processor-Q6700-8M-Cache-2_66-GHz-1066-MHz-FSB

Here is a list of compatible processors,
Max. CPU clock rate     2.66 GHz to 3.60 GHz
FSB speeds     533 MT/s to 1,066 MT/s
Min. feature size     90 nm to 65 nm

Presler P4 915, 2.80G, 2X2MB, 800FSB, D0
Presler P4 915, 2.08G, 2X2MB, 800FSB, C1
Presler P4 925, 3.00G, 2X2MB, 800FSB, D0
Presler P4 930, 3.00G, 2X2MB, 800FSB, C1
Presler PD 935, 3.20G, 2X2MB, 800FSB, D0
Presler P4 940, 3.20G, 2X2MB, 800FSB, C1
Presler P4 945, 3.40G, 2X2MB, 800FSB, C1
Presler P4 950, 3.40G, 2X2MB, 800FSB, C1
Presler P4 960, 3.60G, 2x2MB, 800FSB, B1

Cedar Mill 631, 3.00G, 2MB, 800FSB, C1
Cedar Mill 641, 3.20G, 2MB, 800FSB, D0
Cedar Mill 641, 3.20G, 2MB, 800FSB, C1
Cedar Mill 651, 3.40G, 2MB, 800FSB, D0
Cedar Mill 651, 3.40G, 2MB, 800FSB, C1
Cedar Mill 661, 3.60G, 2MB, 800FSB, C1
Cedar Mill 661, 3.60G, 2MB, 800FSB, D0

Conroe E4300, 1.80G, 2MB, 800FSB, L2
Conroe E4400, 2.00G, 2MB, 800FSB, L2
Conroe E4400, 2.00G, 2MB, 800FSB, M0
Conroe E6300, 1.86G, 2MB, 1066FSB, B2
Conroe E6300, 1.86G, 2MB, 1066FSB, L2
Conroe E6320, 1.86G, 4MB, 1066FSB, B2
Conroe E6400, 2.13G, 2MB, 1066FSB, L2
Conroe E6400, 2.13G, 2MB, 1066FSB, B2
Conroe E6420, 2.13G, 4MB, 1066FSB, B2
Conroe E6600, 2.40G, 4MB, 1066FSB, B2
Conroe E6700, 2.66G, 4MB, 1066FSB, B2
Conroe XE X6800, 2.93G, 4MB, 1066FSB, B2

Smithfield P4 820, 2.80G, 2MB, 800FSB, Mainstream, B0
Smithfield P4 805, 2.66G, 2MB, 533FSB, B0

Kentsfield Quad Core Q6600, 2.40G, 8MB, 1066FSB, G0
Kentsfield Quad Core Q6700, 2.66G, 8MB, 1066FSB, G0
 
Prescott P4 531, 3.0G, 800FSB, 1MB, ALT, G1
Prescott P4 541, 3.2G, 800FSB, 1MB, ALT, G1
Prescott P4 524, 3.06G, 1MB, 533FSB, G1