After reading this thread http://en.community.dell.com/support-forums/desktop/f/3514/t/19379837.aspx
I decided to give it a try and upgrade my Dell E510 from Pentium 4 to Pentium D 945. I upgraded different PC components
in the past, but never a processor. I followed the instructions, removed the heatsink assembly, and
took out the processor, but then I unwittingly scraped off thermal paste from the bottom of the heatsink.
I installed the new processor, put back the heatsink, and tried to start up the computer, but unfortunately
it wouldn't start - no lights come up. I then put back the original processor - same thing, the computer
doesn't start. I read the manual once again, and realized that I shouldn't have removed the thermal paste,
but can that really be a reason for the total failure ? Hard to imagine that a processor can overheat right away -
or is it possible ? I can buy the thermal paste and apply it to the heatsink, but I wonder if anyone has any
opinion or had a similar experience.
I successfully replaced the OEM Pentium D 940 CPU in my E510 with the Pentium D 945. You MUST clean the old thermal paste off of the heatsink and then apply fresh thermal paste when you install the new CPU. Best to use isopropyl alcohol to remove the old paste. Also, a coffee filter works best for removing the old paste. I recommend using Arctic Silver thermal compound.
For me, the upgrade from 940 to 945 was not dramatic. The WEI subscore for the CPU only rose by 0.1 points. But, the D 945 is the best that the E510 can handle so it is what it is. The 945 generates less heat with a TDP of 95 W instead of 130 W for the 940 so that's a plus. Note also that my E510 came with copper performance heatsink because of the higher TDP of the OEM 940.
Upgrading from a Pentium 4 to the D 945 seems like a big jump. There are compatibility issues between the CPU and the motherboard and chipset. My E510 has the right motherboard for the D 945. Other motherboards will require you to press F1 when you boot. I don't have to do that. Moving from a Pentium 4 to the D 945 might not work. Depends on your motherboard.
You certainly do need to remove the old thermal paste and apply a thin layer of new paste as MChiocca said.
But even before you go that far, did you update to the latest version of BIOS before you swapped CPUs? If you have an old version of BIOS, it might not support that new CPU.
In that case, you'll have to put the old CPU back in (with fresh thermal paste), get the PC booting normally and only then flash update to the latest BIOS. Then you can try swapping CPUs, and again remove the "old" thermal paste and use a small amount of fresh paste.
And be sure to double-check all cable connections to the motherboard and drives, reseat RAM and PCI cards in their slots too, in case something didn't get reconnected correctly after the transplant.
Forum Member since 2004
I am not a Dell employee