Date: Tue, 11 Jul 2000 23:29:49 -0700 From: Mike Smith <msmith@freebsd.org> To: "Anthony Rubin" <arubin@concentric.net> Cc: freebsd-hardware@FreeBSD.ORG Subject: Re: Asus K7V with Crucial PC133 ECC RAM Message-ID: <200007120629.XAA00772@mass.osd.bsdi.com> In-Reply-To: Your message of "Tue, 11 Jul 2000 22:28:27 CDT." <006501bfebb1$3ea5df60$b8850140@r2d2>
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Ahh, yes. Well, in this case the amount of memory 'lost' is indeed inversely proportional to the quality of your RAM. The better your RAM, the less capacity that's lost through various coupling issues. You can also improve things by rotating your RAM regularly, and cleaning the contacts with fine wet-and-dry sandpaper every couple of months to reduce oxidation. Also you may find that as your RAM is "broken in" it will regain a little capacity - using a "RAM exerciser" program here can help. Of course, the law of diminishing returns applies as well; spending twice as much on RAM isn't going to result in RAM that only "loses" half as much - there's some "RAM loss" that's just inevitable. Orientation of the system is also important - and if you're really unlucky you can end up with RAM that's designed for use in the southern hemisphere. Due to the manufacturing processes there's always more of it than the northern hemisphere type so the chip makers tend to try to dump it into the channel. Typically the sort of "loss" you're seeing (0.03%) is considered quite acceptable - I'd expect that you can probably soak up at least 10x this with an Enlightenment theme or a neat desktop sound scheme. > I just realized there is an error in my original post. The system reports > 262144K with 256MB installed. This means FreeBSD always reports 80K less. > > ----- Original Message ----- > From: "Greg Lehey" <grog@lemis.com> > To: "Mike Smith" <msmith@FreeBSD.ORG> > Cc: "Anthony Rubin" <arubin@concentric.net>; <freebsd-hardware@FreeBSD.ORG> > Sent: Tuesday, July 11, 2000 10:07 PM > Subject: Re: Asus K7V with Crucial PC133 ECC RAM > > > > On Tuesday, 11 July 2000 at 18:00:55 -0700, Mike Smith wrote: > > >> I recently put together a system that uses the Asus K7V motherboard > with > > >> Crucial PC133 ECC RAM. I bought 2 128MB DIMMs. The BIOS is seeing the > RAM > > >> correctly as 264144K, but FreeBSD has 262064K listed under real memory. > I > > >> thought this was odd and wanted to make sure one of the DIMMs wasn't > bad so > > >> I removed both and then tried one at a time. No matter which DIMM I > use and > > >> which slot I put it in the BIOS sees 131072K and FreeBSD sees 130992K. > The > > >> only other thing that is strange about this setup is that the K7V BIOS > > >> currently has a known problem when you enable ECC so ECC is currently > > >> disabled on my board. Below is the portion of dmesg I am referring to. > > >> > > >>> dmesg | grep memory > > >> real memory = 268353536 (262064K bytes) > > >> avail memory = 256950272 (250928K bytes) > > > > > > There's nothing wrong with your RAM - some of it is being used by the > > > kernel. > > > > I think he's referring to the 80 kB that don't show up in real > > memory. I'd assume that's the BIOS. > > > > Greg > > -- > > Finger grog@lemis.com for PGP public key > > See complete headers for address and phone numbers > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > > with "unsubscribe freebsd-hardware" in the body of the message > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-hardware" in the body of the message > For those of you with no bloody sense of humour, the real reason is that the BIOS has reserved some memory for its own use, as Greg correctly pointed out. If you've studied this entire message for signs I'm on illegal drugs - sorry. 8) -- ... every activity meets with opposition, everyone who acts has his rivals and unfortunately opponents also. But not because people want to be opponents, rather because the tasks and relationships force people to take different points of view. [Dr. Fritz Todt] To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message
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