Overclocking an A64 2800+

[Spiral]

Hey all, I'm new here and I have a question regarding overclocking my computer.
I just recently upgraded parts of my rig for the release of Doom 3.

Currently these are the temps and specs of what I'm running.

The thing is: I can't get much faster than that. Currently, I have the Vcore set to 1.65v and the Vdimm set to 2.5v (default) and the FSB to 222 MHz for a meager increase in overall speed.

Whenever I try to increase the FSB increments through BIOS, it won't load Windows or will just restart at around the 230MHz mark. I have a stock Corsair Hydrocool EX cooling the CPU and I was under the impression that I would have a lot more room to overclock since the temperatures seem relatively low right now...and this is with a side panel removed and a small room fan blowing in the general direction of the case.

Can anyone help me out here? I'm kind of new to this overclocking thing and I wonder if there's something I missed or if I'm just expecting too much.

Here's what I have:

- Athlon 64 2800+
- Chaintech ZNF3-250 mobo
- 512 MB "Ultra" 3200 DDR RAM
- Sapphire Radeon 9600 XT
- TDK Indi DVD 4x DVD+R/RW
- Corsair Hydrocool 200EX
- Seagate 120 GB HD
- Maxtor 80 GB HD
- Hitachi 200GB HD

 

[dabiggoober]

If your temps are accurate, you should have more headroom in OC'ing. You need to increase the voltage to the CPU core to get more cycles though. Raise that 1.65v to 1.75 or even 1.85. As long as you can keep your CPU temps at load less than 50, raise the voltage to CPU as much as it will let you. That should give you a lot more head room to increase the MULTIPLIER. The FSB though, is ram dependant and you might need to decrease the timings on the ram (latency's) to achieve more than the the 220 or 230 FSB you are trying for.

In summary, since that was a little confusing. The FSB determines the speed at which the RAM runs. You getting 220 FSB from PC3200 which runs at stock of 200mhz is good.

You should decrease your multiplier to something low like 8 and then start increasing the FSB to overclock ram until it won't post. Increase the voltage to the ram via the BIOS. Stock is probably 2.6V. Raise this to 2.9 if your BIOS will let you. Then you can find the max FSB speed by going up slowly. You might need to loosen the timings on the RAM as well. The latencies....

After finding your max overclock ram speed....say 233 for example. You can then start upping the voltage to the CPU and increasing the multiplier to get max overclock.

Or since it seems your system is stable at 222FSB already. Try only upping the CPU core voltage to 1.75 and setting multiplier to 10. That would give an additional 222 mhz overclock. If still not stable, up the CPU voltage to 1.8 as LONG AS YOUR COOLING KEEPS TEMPS < 50C, you should be fine.

 

[Spiral]

If your temps are accurate, you should have more headroom in OC'ing. You need to increase the voltage to the CPU core to get more cycles though. Raise that 1.65v to 1.75 or even 1.85. As long as you can keep your CPU temps at load less than 50, raise the voltage to CPU as much as it will let you. That should give you a lot more head room to increase the MULTIPLIER. The FSB though, is ram dependant and you might need to decrease the timings on the ram (latency's) to achieve more than the the 220 or 230 FSB you are trying for.

In summary, since that was a little confusing. The FSB determines the speed at which the RAM runs. You getting 220 FSB from PC3200 which runs at stock of 200mhz is good.

You should decrease your multiplier to something low like 8 and then start increasing the FSB to overclock ram until it won't post. Increase the voltage to the ram via the BIOS. Stock is probably 2.6V. Raise this to 2.9 if your BIOS will let you. Then you can find the max FSB speed by going up slowly. You might need to loosen the timings on the RAM as well. The latencies....

After finding your max overclock ram speed....say 233 for example. You can then start upping the voltage to the CPU and increasing the multiplier to get max overclock.

Or since it seems your system is stable at 222FSB already. Try only upping the CPU core voltage to 1.75 and setting multiplier to 10. That would give an additional 222 mhz overclock. If still not stable, up the CPU voltage to 1.8 as LONG AS YOUR COOLING KEEPS TEMPS < 50C, you should be fine.

Thanks for the info, I appreciate it!

I ended up setting the vDimm to 2.9 like you said and tweaking the latency...
Max Memclock: 166 Mhz
CAS# Latency: 2.5
RAS# to CAS# delay: 3 Bus Clocks
Min RAS# active time: 10 Bus Clocks
Row prechargetime: 3 Bus Clocks
...and I was able to get the FSB up to 240 Mhz and I set the CPU voltage to 1.7V.
Unfortunately, my mobo won't let me change the multiplier so I'm kinda stuck at 9x

I also got a Thermaltake heatspreader and heatsinks for my memory as well.
These are the readings at idle.

If you or anyone else has anymore input, I'd appreciate it. TIA.

 

[dabiggoober]

Good Job!