Would using a modern PSU kill the retro aspect of my LGA 775 build?

Hello. I have all the parts for my LGA 775 build expect the PSU. I wasn't able to find older PSUs on used market, so i'm thinking about something modern. But i'm concerned if it would kill the retro aspect of my build.

Specs:

CPU: Intel Xeon X5450 3.00GHz (modded to LGA 775)

Motherboard: Asus ROG Commando

RAM: OCZ Reaper 2x2GB DDR2-1066MHz CL5

HDD: Samsung HD250HJ 250GB 7200RPM SATA

HDD2: Samsung HD753LJ 750GB 7200RPM SATA

GPU: Sapphire ATI Radeon HD 4870 Toxic 1GB GDDR5 256-Bit

Case: Lian Li PC60