Help progressing my OC! Please read..

[duckdown]

Hi all.
I'm an ABSOLUTE n00b to OC'ing, but a few people have gratiously offered some helpful advice for me to start.

I got an extremely minor OC'ing working completely stable (tested in prime95 for hours, but its an extremely minor OC.) My furthur attempts have all had Prime95 fail instantly with a ROUNDING ERROR.

I have an AMD 3500+ S939 and 1GB of OCZ PLATINUM DUAL CHANNEL RAM (DDR400, 2-3-2-5 the package says), and an ABIT AV8 Motherboard

Stock settings show 204x11, LDT of x5
These are my STABLE OC settings, hopefully you guys can tell me what to adjust to help prime95 to not fail:

STABLE SETTINGS:
DRAM CONFIG: Dram Clock: DDR333
1T 2.5-3-5-2 (i didnt change these, those are what is listed inside of BIOS. However, CPU-Z when the OC is running in windows shows it as 2.5-3-2-5)

LDT: FSBx4
CPU: 233/66/33mhz
Multiplier: x10
AGP: Fixed (66mhz)
Voltages: CPU Core: 1.55
VDDQ AGP: 1.55
DDR SDRAM: 2.70
NB: 1.55
SB: 2.50
HTT Voltage: 1.20


Here are the settings I attempted that are currently failing Prime95. Windows boots and runs fine, I haven't bothered messing with games yet (I figure they wont work if prime95 doesnt, right?)

FAILED PRIME95 Settings:
DRAM CONFIG: Same as above. No changes.

LDT: FSBx4
CPU/Multiplier: 250x10
AGP: Fixed (66mhz)
Voltages: CPU Core: 1.60
VDDQ AGP: 1.55
DDR SDRAM: 2.80
NB: 1.55
SB: 2.50
HTT Voltage: 1.20

Thats what I attempted after the stable 233x10 OC, this one fails. Sorry for the extremely long post, but I would really like to get this 3500+ to at least 2.5

thanks all.

 

[duckdown]

UPDATE: The system is seems absolutely fine at 250x10 except for god damn Prime95.

I have been playing HL2 and CS:S for hours with no stability problems at all, ran Super PI, 3dMark2001SE, all kinds of things. Most importantly, memtest86 ran 15 passes with 0 errors on the overclock! So what on earth is causing Prime95 to fail? Lack of volts? I currently have my CPU CORE at 1.6v, how much farther can I push it SAFELY? I'm using an ABIT AV8 motherboarcd with a good OCZ Powerstream PSU. My DDR SDRAM Voltage is at 2.80 now, and NB is at 1.6v. Prime95 still fails.. HELP!!@#$

I also relaxed the memory timings to 2.5-3-3-5 (they are OCZ platinum modules, rated at 2-3-2-5)

 

[doug_7506]

nm...

 

[sipher]

I was able to run that same ram at 2.8 v 2-3-2-5 all the way up to about 225 then had to start relaxing the timings a bit. I have been able to get it stable on all benchmarks up to 255 mhz 1:1 3-4-4-10. Never tested Prime 95 though.

As long as nothing is going wrong but Prime...keep running those speeds until something goes wrong *shrug*

 

[dabiggoober]

First I would run memtest86 to determine if the 250 speed you have the ram at is the problem or if its your CPU. My guess is the RAM. It IS great RAM! (I have similar series listed in sig) BUT in order to overclock it and maintain good timings you have to really push the voltage into it. That RAM will run at up to 3.3 volts and still not void the warranty. Your MB probably won't push that much though.

Anyway, push the vdimm to the highest your MB will allow, then set timings at something like 2,3,3,(8 or 9 or 10) (a64's tend to like the last number in that range).

Set the multiplier to 8 so that you know it won't be your CPU failing.

Increase your FSB in 5 mhz increments and run memtest each time until it fails.

Then choose multiplier you want, boot into windows and test for prime stability.

Then if system is not PRIME stable, you have a good indication its your CPU limitations and not RAM.

Say this only gets to you 230 at 2,3,3,X and proc is completely stable.

Then relax timings to 2.5,3,3,X and keep upping the FSB till MEMTEST gives errors.

Rinse and repeat. Hope this helps.

 

[dabiggoober]

One more thing. Make sure you have a working PCI lock on your board, and if your're running SATA, that its on the right SATA port. Most boards are picky on that one. For example, mine needs to be on ports 3 or 4 to have my FSB above 229 or so. 1 and 2 will BSOD every time above those speeds.