overclocking a Parhelia

[UtwigMU]

Here's the deal:

When I got my Parhelia, it would overclock flawlessly to 10% (220/275 = retail speeds).

I ran Shark demo for hours without crash.

Now it would lock up in the first test of Aquamark.

(Using MTSTU)

Possible culprits:
1 When I got Parhelia I installed it in PII 350@467. It obviously couldn't push it to limits. The CPU/MoBo was upgraded latter

2 Right now she's roasting under SK7 on CPU2 on my Tyan TigerMPX. Today I added 2 Zalman F2's to blow over CPU2 and over Parhelia. Temps went down 2-5°C (CPU2 59°C under load, AGP 35°).

No improovement

3 I updated to lattest BIOS. This might have changed something.


I'd like to find the culprit-

If I won't be able to take her to retail speeds, that's OK, performance delta is not that big and I won't do a permanent overclock via BIOS.

[Lim]

Single CPU is hot and Dual CPU are very hot. So case ventilation is very important for your Parhelia. For overclock more, you can try open your case cover and use one fan directly blow the P or drill some hole on your case and inhale cool air direct to your P.

For me, I already give up overclock my P. Stability and silence is more important to me.
I can only OC my 256m P to 4% for playing C & C Generals with the case cover opened and one fan blowing the P.

[Wombat]

The processor is going to make a big difference. For example, the G400MAX still saw performance improvements with CPUs up to 800MHz or so, a speed much faster than anything available at its initial release. Also, later drivers may also be more efficient at pushing the card. Heat is also a possibility, but I think the other two are more significant.