Upgrading RAM caused cpu problems

Ok so i had 2GB ram DDR-2 800 and i decided to upgrade and add 2 more.Now i have 4 x 1GB slots dual channel.The thing is after i installed the new ram my pc went slower.The CPU dropped it's performance and it's constantly working on 60%-100%.After i try to start some programs or games things got even worse.I even re-run the windows rating system and i go EXTREMELY low scores on CPU(from 6.0 to 3.7) and on graphics - desktop performance for windows aero(from 7.2 to 2.9).Please help.

My configuration:

Motherboard:Intel DPP3510J
RAM:4GB DDR2 800
CPU:Intel Core 2 Duo E6550 2.33GHz

You need to check the new RAM.Is is tested well or is it compatible with your motherboards..Actually sometimes what happens that quality of product makes big issue..So i think you need to check your new RAM.

Check the RAM timings. Timings are numbers such as 3-4-4-8, 5-5-5-15, 7-7-7-21, or 9-9-9-24, the lower the better. All your memory must have identical timings. If you have different timings you should adjust them in BIOS.

you should check your new ram compatibility with your motherboard,configured it from BIOS.