Hello there. I'm just a newbie in overclocking. can anybody help me with oc?

Original Socket = Intel Pentium 4 2.8Ghz C
Stepping = Northwood
FSB = 200
Clock Speed = 2800Mhz
Voltage = 1.6v
RAM type/timing = GSkill 512x2 Samsung TCCD/2.5-3-3-7

Motherboard
Brand = AsusTek Tech
Model = P4P800 Deluxe
Chipset = 865PE
AGP/PCI-E = AGP

Result
Highest FSB = 250.0*14
Highest RAM = 250.0 (1:1)
Highest Clock Speed = 3500Mhz
Highest vcore = 1.65v
Highest vdimm = 2.85v

Benchmark/Stability
CPU-Z validation = http://valid.x86-secret.com/show_oc?id=39057
Super Pi = 1M calculate : 40s
Sandra = 5262MB/s
3DMARK05 = 2178, http://service.futuremark.com/compare?3dm05=1234018
3DMARK03 = 4643, http://service.futuremark.com/compare?2k3=4267803
3DMARK01se = 14872, http://service.futuremark.com/compare?2k1=8724769

So, is there any way i can do to increase my oc? when i try to increase the FSB to 260, my pc will hang up and need to restart. All sifus here maybe can help me.