G400 MAX duty cycle corrections... help... I have no idea what I'm doing

[CollegeManMan]

I'm using MGAtweak to overclock because I have PD6.00 installed. When I set the SYSPLL to 220 and set the memory divider to 1, the memory works fine at 220 mhz. But if I set the PLL to 330 and have the divider at 1.5, the memory gets flaky at 220 mhz. I've tried messing around with duty cycle correction, but I wasn't getting any results. Eventually I somehow made the screen look like rain was running down it, which scared the crap out of me.

Here's some more information, which might help you guys but it really confuses me. If I set the PLL to 350 and the dividers to 2, everything is fine at 175 mhz (Yeah, my core can do that. Lapped and thermal pasted. What was up with that piece of electrical tape?). Going above that is fine until I try anything 3d, which freezes almost instantly, whatever the dividers are.

Oh, and has anyone tried heatsinks on the ram? I found an old 486 heatsink I can chop up, I'll have that done by the end of the weekend. I really want to reach 175/233. If overclocking trends continue, that would give my settings in Q3 16 more frames per second

[kjliew]

Given that you made it, I doubt it will give you such a boost in Q3 performance. 16 FPS increment in Q3 is huge and almost incredible. No one has ever make it. If you did, let me know.

When you said that your core can make up to 175, and "everything is fine", are you simply looking at the Windows 2D desktop?? It's normal that everything looks great in 2D, but crashed in 3D, because 3D stresses the core/mem more than 2D does. You should not justify overclockability based on 2D, without going through extensive 3D session.

[CollegeManMan]

I tested all those settings extensively in Q3. Outside of Q3, I could get the SYSPLL all the way up to 400, which was the highest I bothered with. When I was testing settings, I would run a demo at regular speed and watch for dots. Then I would run a timedemo for an fps score.

My overclocking trends went like this. With all dividers normal, improvement seemed directly related to memory speed. An increase of 10 mhz brought in 5 fps. +20 mhz gave a 10 fps improvement, but there were many visual artifacts. +33 mhz might bring in 16 fps, but I can't be sure because the memory is very flaky even in 2d at that speed. I have high hopes for my ram-sinks.

My Q3 settings are very customized, and probably entirely dependent on the fillrate of the G400 MAX. Trilinear filtering is enabled, lightmaps are enabled, and texture quality is full. I have also used the \cg_shadows "3" console command to enable stencil buffered shadows. Geometry detail is high. Color depth for everything is 32-bit, of course. I had to give up marks on walls and use \cg_drawgun "0" to get a playable framerate.