Help with G400 overclocking

[SPSUguy]

hey,

I have a vanilla G400 32MB dual head with 6ns memory. Using powerstrip I am able to overclock to 138 core, 184 mem before I notice any problems. Using the Matrox overclocer, I can set to 110% before problems occur (which I believe is about the same).

As far as cooling, it just has the standard heatsink. I have a super slot cooler below the G400 sucking air out of the case. I figure it is pulling air off the G400 as well. I was just curious how much help it would be by adding at 486 fan to the heatsink. Anyone else have much experience in this area?

Thanks for your help

[Nuno]

What problems do you have above 138/184? If it´s something like hard lock-ups, or a totally mess in the screen before it locks up, you probably are reaching the core limits. More cooling (a fan over the heatsink) could defenitly help. If what you see is colored dots and lines moving around, the memory is maxing out. Then there isn´t much to do.
Either way, I think 138/184 is not very much. I can run my vannilla at 153/204 before memory corruption appears in the screen. I run it usually at 150/200 (just to be on the safe side) with a pentium fan glued to the heatsink.
But hey, in overclocking there is no guarantees at all. You bought a 126/168 card and if you can´t clock it higher you can´t complain But with almost all people reaching above 140 core maybe you just got a not-so-good card. It happens.

[DuRaNgO]

also, the slot fan can sometimes be a detriment as it pulls pre-heated air from the case over the card, be sure you have enough intake fans to compensate
jim

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PIII-500mhz @ 620!, Abit BE6 mobo, 128mb pc-100, Mill G200(still!!!) 8mb sgram @ 210 with MGATweak) PD 5.25, Maxtor 13.2 gb Uata66 hdd, SB Live!, winblows 98se, DX7, THREE BIG FANS, six little ones and a case that sounds like a turbine engine...doh!

[Zagarus]

I run my G400 16mb SH at 150/200 and I don't even have problems with heating. I got 486 fan over heatsink so I guess its working pretty well. Altho for some reason my machine likes to think this as PCI device..any ideas why it thinks so? I have tried pretty much everything I know to no avail.

[G.M.E.]

I'm pulling 162/216 with a vanilla G400 32meg using a Card Cooler. This is 128% on the Matrox slider. Anything over that and I start getting lines of blue dots on white screens... FWIW Seems like our milage varies.

[gbm]

Memory is the probable source of your problems. To overclock it this high you need to change some parameters and then increase the clock speed. If you use MXINFO from my website to get the default parms and then play a little with memory optimization in MGA Tweak to relax the memory settings, you should be able to achieve 200 MHz memory clock.

[Nuno]

Zagarus: I´m not sure if I fully understood your problem. When windows 9x detects the card it will recognize it as a pci vga display device or something like that. That is normal.

But if you are using win 95, you need that usb patch from microsoft that also enables agp support in win 95. And it only works for win 95 osr2. Win 98 natively supports AGP.

[SPSUguy]

Hey,

As soon as I go over anything over 138 core, I start to get these little white lines over part of the screen. (Actually, this kinda scares me ) So guess this means I got crappy memory Is there anyway that I can cool the memory or chop up some heatsink and apply it individually to each of the memory chips?

Could someone delve more into the settings i could use for mgatweak?

And whoever mentioned that webpage above, could you please post a link?

thanks

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Abit BH6, Celeron 450, Matrox G400 32mb, 256mb ram, IBM 10GB, DVD 5x, MX300

[SPSUguy]

Hello again,

GBM, I found your website. But the link to the mx program and all the other utilities are broken. Anywhere else I could get it?

Thanks

[SPSUguy]

Hey,

I went to Radio Shack to get a 486 fan for the G400. I didn't buy it because it looked to small. Would it be better to get a pentium or larger fan? Or the the 486 fan good enough?

Thanks

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Abit BH6, Celeron 450, Matrox G400 32mb, 256mb ram, IBM 10GB, DVD 5x, MX300

[Cloudy]

Try using a Socket7 (pentium mmx) cooler, it's almost the exact size so u can screw it real nice

[Zagarus]

Nuno..I have win98 and I have been using AGP vid card for over a year now..up until now I have had no problems with it. Few days ago however my machine just suddenly decided that my card is no longer AGP device..thats it. Even have had G400 for over a month now.
for instance..I no longer can benchmark my card with 3dmark using AGP features. Now my texture memory is what it would be without AGP. not to mention test results dropped down drastically.

[This message has been edited by Zagarus (edited 10-10-1999).]

[Ali]

Im using 2 cyrix X86 fans. Theya re about 4cm square, and only cost about $10 (US$5ish)

If you cut the heatsinks in half, they fit on the memory chips fine. Im using dick Smith heat transfer glue to hold them on.

The two fans are both attached to the heatsink using screws that I cut to length. One of the fans overhangs towards the TVout chip (or what ever that little chip with the cute little heat sink is).

I can run at 178 core and 240 ish mem (from memory, Im at work, and cant check the exact numbers).

Most of the time I run at 220mem using powerstrip though.

Im not sure, cos I have the heatsinks glued to the memory, but Im guessing I have the 5n RAM

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[SPSUguy]

Hey,

Not sure if you read my other post, but I raised my resolution to 1152x864 and now my g400 overclocks to 150core/ 200mem with no problems and no extra cooling. I'm still going to get a pentium fan just to be safe.

I haven't tired to clock it any higher though. I figure I'd be pushing my luck. Besides, just how much more performance could I ask from this thing???

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Abit BH6, Celeron 450, Matrox G400 32mb "MAX", 256mb ram, IBM 10GB, DVD 5x, MX300

[SPSUguy]

Ok... update time. Got my pentium fan and put it on the heatsink. Here's the deal... i should have gotten the 486 fan. the pentium fan is too big. Therefore I only have two screws holding it in. I think it'll be ok.. but I'd feel better with all four screws in.

I'm not sure how bold i feel, but i think i'll try to overclock even more. Currently at 150core/ 200mem. But i may be pushing it. Just how high can 6ns memory go anyway? I forgot the formula i read on anandtech.

Also, i've heard some people say that they have performance decreases the more they overclock. What's up with that?

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Abit BH6, Celeron 450, Matrox G400 32mb "MAX", 256mb ram, IBM 10GB, DVD 5x, MX300

edit: originally said 5ns memory... i think it's actually 6ns. The maxes have 5.5ns if i remember correctly.


[This message has been edited by SPSUguy (edited 10-12-1999).]