From owner-freebsd-alpha Mon Aug 9 15:57:22 1999 Delivered-To: freebsd-alpha@freebsd.org Received: from picnic.mat.net (picnic.mat.net [206.246.122.133]) by hub.freebsd.org (Postfix) with ESMTP id 0AC41152C3 for ; Mon, 9 Aug 1999 15:57:01 -0700 (PDT) (envelope-from chuckr@picnic.mat.net) Received: from localhost (chuckr@localhost) by picnic.mat.net (8.9.3/8.9.3) with ESMTP id SAA19568; Mon, 9 Aug 1999 18:53:09 -0400 (EDT) (envelope-from chuckr@picnic.mat.net) Date: Mon, 9 Aug 1999 18:53:09 -0400 (EDT) From: Chuck Robey To: Thor Lancelot Simon Cc: alpha@freebsd.org Subject: Re: Installing the heatsink In-Reply-To: <19990809181756.A10485@rek.tjls.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Mon, 9 Aug 1999, Thor Lancelot Simon wrote: > On Sat, Jul 31, 1999 at 04:38:22PM -0400, Chuck Robey wrote: > > My alpha came with a heatsink that has what seems to be a thin lead > > gasket, between the processor and the heatsink itself. I've never used > > one before; I've always used silicone grease. > > The gasket is not lead, it is grafoil. If you've handled it with your > bare fingers, it's possible that you've damaged it and will need to > obtain a new piece -- it is allegedly very susceptible to contamination > with skin oils. > > > Does anyone know if I should use that gasket, and (if so) how should I > > think use the silicone grease (if at all)? Is there any rule of thumb > > about tightening down those two bolts that connect the heatsink to the > > processor? > > Do *not* use silicone grease. You need to use the correct grafoil > gasket, installed without handling with your bare hands (I actually > just clean my fingers with isopropyl immediately before handling > the gasket, and make sure they're dry, but gloves are a better idea > unless you have a large number of surplus alcohol wipes handy :-), > and cranked down with *the nuts that came with the heatsink kit* to > the correct pressure, using a calibrated-torque driver. If you've > done a large number, you can probably get a feel for "the correct > pressure", but if not it's best to use the proper tool. > > This is not unlike installing a head gasket in your car's engine -- if > you screw up, you may not find out until something suddenly blows. The > Alpha puts out a lot of heat, and that grafoil gasket, installed and > compressed properly, gives it a nice uniform path out the top of the > processor, with no hot or cold spots. Other methods don't do that, and > may lead to sporadic misbehaviour that's nearly impossible to diagnose, > once enough time has passed for it to develop. > > Gasket, heatsink, and nut specifications and torque values are in the > thick version of the technical manual for your Alpha motherboard. I > can also supply them by email if you don't have or can't get that. I had handled it a *little* before I got the advice (you took about 2 weeks more than other to reply, you must be a little behind in your mail). I'm going to go ahead and install it now, but do you know of a vendor for the grafoil, so that I can eventually replace it? BTW, getting those little nuts on, inside the heatsink, well it's the kind of things you damn the designers for. > > ----------------------------+----------------------------------------------- Chuck Robey | Interests include any kind of voice or data chuckr@picnic.mat.net | communications topic, C programming, and Unix. 213 Lakeside Drive Apt T-1 | Greenbelt, MD 20770 | I run picnic and jaunt, both FreeBSD-current. (301) 220-2114 | ----------------------------+----------------------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message