Hi everyone. I just picked up a extra DC today at the thrift shop. It didnt have any cables with it so the best I could do in the store was to use a radio cord to power it up and put in a audio cd to see if it spun. While it does spin its by far the quitest DC I have ever heard. I got it home and it wont read disks but thats not to big a problem to fix. Anyway This one is beat to hell so its getting sanded, primered, and a nice paint job. I also plan to led mod it and such. My big question is on the PCB itself on the SH4 chip and the other one there are little like patchs on the top that are like funny feeling stickers. I know they help conduct the heat up to the metal heat sink mounted on the bottem of the metal shielding. Im wanting to know if I remove those patchs can I mount a video card heat sink and mini fan to the top of them with thermal paste? If anyone has done this or has any ideas please let me know. I also plan to try and mount little heatsinks to the ram chips with thermal paste. :rambo:
Cooling? You always want to mount a heatsink as close as possible to the thing you are trying to cool so it would probably not be wise to mount a new one unless you do it directly on the core or its heatspreader(if it has one) and not on top of some old thermal interface material. It may also a good idea to use some high end thermal paste such as Arctic Silver 5 if you put on a new heatsink.
you definetely should not use the old thermal grease, but you dont need as5 for a flippin' dreamcast. If you figure out a way to mount it directly on to the chip with some thermal paste it should be fine though. The big problem is finding a way to mount it.
Thanks for the replys guys. Im saying will I be ok if I remove the little heat patch things and just mount the sinks right on the chips? I know I will be fine on the SH4 chip since its normal but the power VR2 has little recesses in each corner. I dont think that getting paste in these little recesses will hurt anything but it still has me a little worried. I dont need anything like to screw it into do I. I thought that when the paste drys it would do a fine job of holding the sinks in place? Is that a correct assumption? Any more info or ideas are greatly appricated. Thanks again for all the help ;-)
The paste shouldn't ever dry... Depending on what brand you're using, it should hold a pretty good tack, but i wouldn't rely on the past alone to hold the heat sinks in place. In the past i've used super glue to hold sinks in place, but i don't recomend it, as some brands contain acetone and will eat through circuits.
The other problem with the idea is that superglue, like most standard adhesives, is fairly sensitive to heat. If the chip runs hot your superglue could be rendered useless in a fairly short time; even if the chip only gets warm, it's still going to reduce the longevity of your glue. Plus, superglue isn't a very good conducer of heat. Thermal pastes like Arctic Silver and other brands are designed with these issues in mind - they hold your heatsink in place and are excellent conductors of heat from the chip to the sink. It's probably not a good idea to experiment with any other substances unless you've got another Dreamcast in case this one craps out - and unless you don't mind the slight possibility of fire.
I was never thinking of using super glue. I was just calling into question weather or not thermal paste alone would hold the heat sink and its fan in place? Im using fans off of old video cards (and heat sinks) and they were only held on with the paste so I dont really see a problem. Im just a little scared that the fan spinning will move the heatsink around and possably vibrate it off the chip. Theres nothing really to screw it down onto so using the paste to hold it in place is really my only option. I do have 2 other DC units but this one is beat to hell so its perfect for this kind of thing.
Adhesing The really permanent option ProgrammingAce mentioned would be Arctic Silver's Alumina Epoxy or Silver Epoxy - really I'm sure either one would work perfectly fine. As you noted you'll have fan vibration and that's really what would drive me to use epoxy the most... it'll be a pain but since you've decided to chang the heatsink you may as well do it right. ~Krelian
