Same PC Mark score DIFFERENT hardware!!

Hey i am somewhat disappointed in somethign i ran into. I have built two computers. One for my brother and one formyself.
Asus p5q3 deluxe 215 dollars ( fsb 460 1840mhz)
ram- ddr3 1066 ocz ( running at 920mhz for 1to1 ratio)6-6-6-18
cpu- q6600 ( oc 3.7 fsb 460)
gpu- asus 4850
harddrive- sata seagate 80gb raid 0
ratio 1:1

Msi cheap 80 dollar mobo ( fsb 400 1600mhz)
ram- ddr2 1066 ocz ( running at 800mhz for 1to1 ratio) 4-4-4-12
cpu- q6600 ( oc 3.2 fsb 400)
gpu- asus 4850
harddrive- WD 500gb sata
ratio 1:1

my problem is my computer components are much better mostly speaking about motherboard, and ram and not to mention the fact mine is overclocked to 3.7 and my brothers is overclocked to 3.2. i ran PCMARK 05 and i got the same scores, it was 10997/ 10993 give or take each run. I dont see how these these two computers are running at the same speed. do you think something is bottlenecking my computer and stopping it from going faster. anyone know anythign about this?...bc the stats are clearly different, mine is much overclocked then my brothers but are having the same pcmark scores

1091

1093