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From: khoult@bbn.com (Kent Hoult)
Newsgroups: sci.electronics
Subject: Re: 1Mx9 DRAM, Should New Design use SIMM or SIP ??
Message-ID: <61997@bbn.BBN.COM>
Date: 10 Jan 91 17:32:13 GMT
References: <1991Jan10.170127.9293@cbnewsc.att.com>
Sender: news@bbn.com
Organization: Bolt Beranek and Newman Inc.
Lines: 34

In article <1991Jan10.170127.9293@cbnewsc.att.com> tjr@cbnewsc.att.com (thomas.j.roberts) writes:
>I am designing a new board that uses 1 Meg by 9 DRAMS. Clearly,
>it is cheaper (and uses less board space) to use regularly-available
>SIMMs or SIPs than to use individual chips. These SIMMs and SIPs
>are used in scads of PC clones, PS/2s, Macs, etc.; they are often
>cheaper than 9 1Mx1 DRAM chips.
>
>Question: Which should I use, SIMMs or SIPs ??
>
>What are the advantages/disadvantages of SIMMs and SIPs ??

SIPs
      -	they are slightly less common than SIMMs
      -	they are soldered in, so adding/removing modules is harder
      + they only mount vertically, this lets you mount them 
	as close as 0.3" apart (maybe 0.25").
      - They only mount vertically, needing more height.

SIMMs
      - They need a socket, this costs money.
      + They need a socket, this makes them easy to add/remove.
      + The sockets are available in vertical, angled, and horizontal
	mounts.
      - The angled mount sockets can't be spaced closer than 0.5" apart,
	so more board space is used by them.
      + They are slightly more common and are easier to produce than a SIP,
	so they should be a bit cheaper.

  These are the main points I could remember of off the top of head. I've
designed boards using both, and these were the main factors.
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