New Overclock

My first system build and first try at OC'ing, and have reached impasse.
System specs in signature.

Current settings using Abit bios terms:
CPU Operating Speed: User Defined
External Clock: 400Mhz
Multiplier: x7
New Clock Speed: 2800
DRAM Speed (CPU : DRAM): 1:20 DDR2 960

Voltage Control: User Define
CPU Core Voltage: 2.38v
DDR2 Voltage: 2.20v
CPU VTT 1.35 Voltage: 1.35v
MCH 1.25V Voltage:1.52v
ICH 1.05V Voltage: 1.38v
ICHIO 1.5 Voltage: 1.50v
DDR2 Reference Voltage: 0%
CPU GTLREF 0&2: 67%
CPU GTLREF 1&3: 67%

DRAM Timing Schedule: Manual
CAS: 5
tRCD: 5
tRP: 5
tRAS: 15
Command Rate: 2T
Rest of settings left on Auto

At these settings, system rock-solid with MemTest, ORTHOS and Prime 95.

CPU Temperatures/Fan Speed under load: <35C/1500RPM
System Temperature: <40C

Problem-When I start to adjust DRAM Timing to GEIL specs of 4-4-4-12, I start getting problems, ranging from MemTest Errors, & BSOD to faliure to boot, e.g., at 4-5-4-15 2T, system wouldn't boot. Is this a voltage problem, DRAM Speed, External Clock, or... ?

Questions: I value stability over speed. Am I better off with aggressive MHz settings, and conservative DRAM Timings or the reverse...or neither?

Hope all this makes some sense, and I welcome all comments and suggestions.

Thanks

DRAM timings are not noticeable unless you are benching super pi, so just go for the relax timings 5-5-5-15.

Isn't that memory rated for 4-4-4-12 @ 800? At 960 you'll most certainly have to relax the timings. 5-5-5-15 should get you through any booting issues. You're best bet is to check out Geil's forums or email their support. They'll help you get your memory to where you want it. They helped me get my Geil up to 1066 at pretty decent timings.

FWIW, since you're running at 400mhz FSB why not just run the ram at 1:1 4-4-4-12? You're not really going to notice a difference between 800 and 960 and your ram will stay cooler.

HydroBudz said:

Isn't that memory rated for 4-4-4-12 @ 800? At 960 you'll most certainly have to relax the timings. 5-5-5-15 should get you through any booting issues. You're best bet is to check out Geil's forums or email their support. They'll help you get your memory to where you want it. They helped me get my Geil up to 1066 at pretty decent timings.

FWIW, since you're running at 400mhz FSB why not just run the ram at 1:1 4-4-4-12? You're not really going to notice a difference between 800 and 960 and your ram will stay cooler.

Click to expand...

Thanks for taking the time to respond- FYI-According to CPUZ-SPD the 4-4-4-12 frequency is 266Mhz, and the 5-5-5-15 is 400Mhz,

To your next point, I take it to mean-leave my external speed at 400Mhz, reduce my DRAM speed to 800 (1:1), and then set my timings to 4-4-4-12? If I have that right, does the preceding FYI change your suggestion at all?

bail_w said:

DRAM timings are not noticeable unless you are benching super pi, so just go for the relax timings 5-5-5-15.

Click to expand...

Thanks for responding-I may in fact do that, as my interest in OC'ing is one of want rather than need.

I would go far as i could with the stock timings and leave it there. Unless you're going to try to bust large number isn benchmarks then i would go for a higher fsb and loosen a bit up on timings. But my G-Skill pc6400 with stock timings of 4-4-3-5 will go over 1,000 fsb with those timings and no volt increase. luck of the draw i guess.

Good Day

CPUz reports my Geil as having those same timings as well. They do that so people can plug them in and POST on the first power-on without stability issues.

I would just leave the timings at 5-5-5-15 and be done with it.