VOGONS


First post, by stealthjoe

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I have removed the original heatsink from a V3 card and cleaned up the existing thermal paste. The compound on the existing heatsink is in the form of a thin sheet (~1 mm ). Then proceeded to apply MX4 using the pea method after cleaning the core and the heatsink. After applying the compound, attached the heatsink. I did notice a bit of a play on both the diagonal screws despite fully locked in. My query is, could we use a paste based compound like MX4 (which has negligible thickness) as the original thermal pad is a bit thicker. Can it affect the heat transfer performance significantly? Let me know your thoughts? Thanks.

Intel 845GEBV2, Pentium 4 2.4 Ghz, Geforce FX5600 256MB, 512MB RAM, 160GB HDD, Sound Blaster Live! SB0100 - Win 98/XP

Reply 1 of 6, by appiah4

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If the heatsink is wobbly that means it is not making proper contact anymore. This is normal since the original heatsink height probably takes into account the thermal pad thickness. Your options are to mount a third party heatsink that can be tightened down better, or a thicker thermal pad. Using it the way you describe will probably damage the card.

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Reply 2 of 6, by bloodem

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stealthjoe wrote on 2023-01-26, 07:47:

I have removed the original heatsink from a V3 card and cleaned up the existing thermal paste. The compound on the existing heatsink is in the form of a thin sheet (~1 mm ). Then proceeded to apply MX4 using the pea method after cleaning the core and the heatsink. After applying the compound, attached the heatsink. I did notice a bit of a play on both the diagonal screws despite fully locked in. My query is, could we use a paste based compound like MX4 (which has negligible thickness) as the original thermal pad is a bit thicker. Can it affect the heat transfer performance significantly? Let me know your thoughts? Thanks.

Ouch. You need to measure the temperature on the back of the PCB, right behind the "GPU" core. Typically, it should not exceed 70 degrees C.
As for MX4, that thermal paste is MUCH more powerful than the original thermal glue on that card (if the heatsink is seated properly, that is).

1 x PLCC-68 / 2 x PGA132 / 5 x Skt 3 / 9 x Skt 7 / 12 x SS7 / 1 x Skt 8 / 14 x Slot 1 / 5 x Slot A
5 x Skt 370 / 8 x Skt A / 2 x Skt 478 / 2 x Skt 754 / 3 x Skt 939 / 7 x LGA775 / 1 x LGA1155
Current PC: Ryzen 7 5800X3D
Backup PC: Core i7 7700k

Reply 4 of 6, by stealthjoe

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appiah4 wrote on 2023-01-26, 09:00:

If the heatsink is wobbly that means it is not making proper contact anymore. This is normal since the original heatsink height probably takes into account the thermal pad thickness. Your options are to mount a third party heatsink that can be tightened down better, or a thicker thermal pad. Using it the way you describe will probably damage the card.

The heatsink isn't wobbly. However, the two diagonal locking pins have a very small play on pushing it alone. I assume this is already present in the unmodified V3. Could someone please confirm it?

Intel 845GEBV2, Pentium 4 2.4 Ghz, Geforce FX5600 256MB, 512MB RAM, 160GB HDD, Sound Blaster Live! SB0100 - Win 98/XP

Reply 6 of 6, by Doornkaat

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It's normal to be able to push the heatsink around a bit if you replace the thermal pad with paste. Don't worry. Press the heatsink firmly onto the chip, don't rely on the pins alone to initially squeeze the heatsink on the chip and spread the paste between them into a thin layer. Once the paste is spread well it does a well enough job holding the heatsink on the chip with the pins preventing it from sliding around.