G200 Overclock, how far?

[istymie]

I've been able to use my homebrew watercooling setup to get my G200 SGRAM board up to 266Mhz core (had to use /2 on MCLK=133). Anyone know what the G200 core is capable of? Is 266 a decent overclock or just average? Seems to hit the wall around 283, mainly because the RAM can't handle anything more than about 140 Mhz.

[Guru]

Had mine at something like 105 core 140 memory (used a p2 heatsink)!

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[rubank]

Sorry istymie,

but your core numbers are totally wacked. There is no hope in hell (or elsewhere) that your G200 runs at that speed.

Tell us what o/c prog you´re using, and maybe someone will tell you what is wrong with your readings.

rubank

[istymie]

I was using the version of G200CLK here on the matroxusers site. I started at 183 and worked upward. The memory on the card hit the wall at about 143Mhz so I had to use the /3 parameter to set the MCLK divider to 2 (from 1.5) this lowered the memory speed and allowed me to continue upward until I hit 283. At 283 the system froze after a few moments so I backed it down to 266.

I was using the command lines:

G200CLK /3 2 2 2
G200CLK /2 1 0 4 0 0 0 0 0 0 0 0
G200CLK /1 266

When I ran G200CLK after these commands were issued, it reported back all of the correct numbers (266, 133MCLK etc.) Seems strange that the program would seem to work correctly, but still let me achieve such high numbers.

I say all of this in the past tense because I have now switched over to a G400 (non max) which I have the core at 333Mhz (MCLK divider is 2.0 again yielding a 183 Memory clock. I am not sure that this is a decent O/C for a G400 or not. Anyone?

I have put up a copy of my G400 MGATweak screen at http://home1.gte.net/bs/m400oc.jpg for anyone who cares. A picture of the homebrew watercooler system I am using is at http://home1.gte.net/bs/hbwater.jpg just in case anyone wants a good chuckle. I built all of the waterblocks on my cheesy drill press which is why they look so crude. Using a 250GPH aquarium pump to circulate, no radiator at this time, no peltiers.

-Bryan

[arbymo]

i have a G200 8 M SDRAM.
i can go as high as 240 for the PLL clk which leads to 160 memory and 120 core.
but i use a safer o/c to 225 due to not enough air and hot room.
u shouldn't change the divider .. just leave em at 1.5 for ram and 2 for core.
i don't have a G400, but i believe most guys here can go as high as 200 for the memory.
so i guess u can higher with ur G200 and G400

[istymie]

My mistake, I was quoting the PLL clock as the core clock. Now it makes much more sense. So the MCLK is the memory and WCLK is the core clock then?

[Maggi]

I had a Mystique G200 that was willing to go up to 164MHz mem clock, using Powerstrip

[anid]

No, the G clk is the core... the W clk is the Warp, but they should always be the same thing with a G200. I've managed to get my G200 SD 16MB to 248 PLL (artifacting), 246 (minor glitches), 242 (free and clear), using only a Tennmax Lasagne cooler and some small RAM sinks made from an old 486 cooler. I thought 250 PLL was the limit on 'em, so I'd say you got that mug as high as it's gonna go.

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"I wrestled with reality for 27 years and I'm happy to say I finally won out over it."

[Livius]

Hi! My Compaq Mill G200 8MB went as high as 120/160 core/mem.

[Job]

Whats the benefit of overclocking the G200

I have an 8MB G200 Mystique...with the Rainbow Runner Studio Setup.
If I can get my refresh rates up - that would be good since I run at 1200x1024 and only 60Hz...

Also - How do I do it?

[Alec]

Job, you mean 1280x1024...
I think that the chip´s speed has nothing to do with refresh rates. The RAMDAC´s speed has.
The Mystique G200 is capable of much more than 60Hz at 1280x1024... your monitor must be the limit. Check this:

http://www.matrox.com/mga/products/tech_info/refresh_rates.cfm

My G200 ran at 105Mhz core max. with a Cyrix cooler on top. Its default core speed was 90Mhz only.

[Wombat]

My G200 would do 205 at first. I took off my G200 Millenium's heatsink, put in some Arctic Silver, and a 486 fan/HS. Speed went up to 212-215.