problem when upgrading ddr ram

Hello all!
Here's my system:
VPR matrix FT9150-PE
Intel MB - d845pebt2
all original except:
XFX nvidia geforce 6800 gt xtreme
upgraded memory to 1gig of ddr 333

earlier this week i decided i wanted more ram, and i found a deal on some ddr400 on new egg. i bought it, when it arrived i read through the manufacturers website, and the highest the mb accepts is ddr333. so i searched around the net and found out that ddr ram should be backwards compatible and the system should just underclock the ram to ddr333 standards, or so i thought from what i read. so i slap in the new ram, confident it will work, and turn on the computer. the cdrom and activity leds on the front of the case stay lit, but no splash screen, no post code, no nothing. so i decide to try the old ram again, nothing. the computer will no longer do anything but light those 2 leds. fans are functional and the green led on the motherboard is lit, telling me the mb has power. i've stripped the computer down to cpu trying to see if one of the part had gotten damaged in my escapades, but to no avail. i even reseated the cpu and fan, and tried all combinations of the old ram i could (one stick in either slot, and both sticks in) still nothing. i tried taking out the cmos battery to reset it and still nothing. intel's website says you can recover the bios if it was corrupted, but there is no link to the proper software/bios file. plus the computer doesn't even come to the post part of startup, so how would i change the bios?
did i fry my computer? is there anything else i can try? any help would be greatly appreciated. and sorry for the massive runon paragraph

thanks for any help you can give me,
Cool#9