A friend gave me his old computer without the hard drive. The exact reference on the sticker is: Compaq D3vm/P 1.6/20/k/128c FR (french computer)
I can't found ANY information about this model, all google searches show me the same motherboard but with socket 370+sdram or lga775+ddr2 (it's NOT an EVO product, there's no front usb)
I've found an ebay auction with the same computer (the desc is wrong, it's not DDR)

After opening it here's the motherboard.

The CPU is a Intel® Pentium® 4 Processor 1.60 GHz, 256K Cache, 400 MHz FSB.
Memory is SDRAM type (pc100 or pc133, ecc is not recognized) i don't know the chipset for the southbridge/northbridge.

Socket 478 can accept Northwood and Willamette.
I've got these old cpu from my previous computers:
1x Intel® Pentium® 4 Processor 2.40 GHz, 512K Cache, 400 MHz FSB
1x Intel® Pentium® 4 Processor supporting HT Technology 3.20 GHz, 512K Cache, 800 MHz FSB

Can i replace the 1.6gHz safely with those ? I've some concern about the 800 FSB, i don't know if it will work (i remember using DDR with my P4 3.2 HT)

Thanks