I have an E510 which is identical to the 5150 (the only difference the E510 was only sold in the US and the 5150 was sold everywhere).

I'm surprised that it even works, let alone the "incompatible processor".  The Dell implementation of the Intel Chipset is not the full impementation that is available - you are limited to the Dell custom implementation.  The Intel listing for this chipset, which supports Dual P4 processors says it will accept up to a D960 CPU however the Dell implementation limits that to a D945 (we have documented cases on the old Dell users forum).   Another issue is that Dell used several different part number motherboards and with compatible CPU's on all the motherboards except the 0HJ054 part number board, even if you install a fully compatible upgraded CPU you wil still get the Incompatible CPU and will have to press F1 to continue (and it will work OK).  The clock speed of the processor is limited by the Dell custom implementation and the BIOS which does not allow overclocking.

You will do just as well to reinstall the original CPU and try to return the new one.  

I upgraded my E510 from the original D805 CPU to a D925 CPU and to be truthful it was a waste of $$.  I have the 0HJ054 motherboard so I don't get any incompatible CPU notices.

Thanks for the reply.

I dont think i explained myself very well,the processor im trying to upgrade to is a  P4 670 3.8Ghz as suggested by shesagordie in an earlier post,not a Dual P4.

Here is the report from cpuz on the processor if thats any help.Please bare with me as i have little knowledge when it comes to processor,as you have probably noticed.

Processor 1   ID = 0
 Number of cores  1 (max 1)
 Number of threads 2 (max 2)
 Name   Intel Pentium 4 670
 Codename  Prescott
 Specification  Intel(R) Pentium(R) 4 CPU 3.80GHz
 Package (platform ID) Socket 775 LGA (0x4)
 CPUID   F.4.3
 Extended CPUID  F.4
 Core Stepping  N0
 Technology  90 nm
 Core Speed  2793.1 MHz
 Multiplier x FSB 14.0 x 199.5 MHz
 Rated Bus speed  798.0 MHz
 Stock frequency  3800 MHz
 Instructions sets MMX, SSE, SSE2, SSE3, EM64T
 L1 Data cache  16 KBytes, 8-way set associative, 64-byte line size
 Trace cache  12 Kuops, 8-way set associative
 L2 cache  2048 KBytes, 8-way set associative, 64-byte line size
 FID/VID Control  yes
 FID range  14.0x - 19.0x
 VID range  1.116 V - 1.436 V

I don't have that much knowledge either but the problem I see is the 3.80GHZ version, and possibly the part number motherboard you have that will give you incompatible processor. 

Maybe Bev will chime in with more info.

If this is any help...It appears that if you have one of these boards (of course this is eBay research :emotion-1: ):

RD203,KF623,J8885,WG261

Then the supported processors are:

• Pentium 4 Processor 570J supporting HT Technology (1M Cache, 3.80 GHz, 800 MHz FSB)
• Pentium 4 Processor 561 supporting HT Technology (1M Cache, 3.60 GHz, 800 MHz FSB)
• Pentium 4 Processor 550 supporting HT Technology (1M Cache, 3.40 GHz, 800 MHz FSB)
• Pentium 4 Processor 541 supporting HT Technology (1M Cache, 3.20 GHz, 800 MHz FSB)
• Pentium 4 Processor 630 supporting HT Technology (2M Cache, 3.00 GHz, 800 MHz FSB)
• Pentium 4 Processor 521 supporting HT Technology (1M Cache, 2.80 GHz, 800 MHz FSB)

•  

Be careful, Intel lists what the "Retail" chipset is compatible with.  Dell uses a custom implementation and not every CPU that Intel lists will work in a Dell motherboard.

I have the 0HJ054 motherboard, which was the latest (last) motherboard used, which does not give the "incompatible CPU error" on compatible CPUs, and it won't support everything that Intel lists.  The Dell motherbords are Dell custom models (many made by Foxconn for Dell).

CAN I GET ANY VERIFICATION ON THIS PLEASE

RD203,KF623,J8885,WG261

Then the supported processors are:

• Pentium 4 Processor 570J supporting HT Technology (1M Cache, 3.80 GHz, 800 MHz FSB)
• Pentium 4 Processor 561 supporting HT Technology (1M Cache, 3.60 GHz, 800 MHz FSB)
• Pentium 4 Processor 550 supporting HT Technology (1M Cache, 3.40 GHz, 800 MHz FSB)
• Pentium 4 Processor 541 supporting HT Technology (1M Cache, 3.20 GHz, 800 MHz FSB)
• Pentium 4 Processor 630 supporting HT Technology (2M Cache, 3.00 GHz, 800 MHz FSB)
• Pentium 4 Processor 521 supporting HT Technology (1M Cache, 2.80 GHz, 800 MHz FSB)

CAN ANYONE VERIFY THIS INFORMATION