I have the Asus P2B-D and ran into the same problems.
2 Slot1's with Slot1 GORBs BARELY fit but my slockets w/ socket GORBs didn't.
The LP alphas look kewl but I couldn't get myself to pay that much for 'em.
I ended up buying 2 Low Profile GORBs for 9 bucks each.
I am not doing extreme overclocking and my case has decent airflow so they work fine.