The real issue is that if you were buying RAM from some of those truly hole-in-the-wall vendors often what you were essentially getting was daily spot pricing on a very fluid commodity. It's totally possible on the day you ordered your SIMMs in May 1990 they cost $45 while if you'd called at the same time next month they would have been $60. Many of the ads for RAM in the contemporary magazines for which archives exist (Byte, MacWorld, PC Mag... unfortunately Computer Shopper seems to be lost to history) simply say "CALL" instead of printing prices at all. I'm just listing the lowest prices *I see in print* because that's the only data point everyone can track.I wish I had a Computer Shopper from 1990. I'm not nitpicking RAM prices, just going with what I've got printed out here.
One thing I will note, though, is that in a May 1990 Macworld that the same company that was asking $130 for 2x2MB SIMMs in October was asking $254 for it in May 1990. Same company wants $98 for in May 1991, and also only wants $910 for the 16MB kit, so memory *really* went down in price a few months after the LC was introduced. Are you *sure* you bought your 386sx the day Windows 3.0 came out, not Windows 3.1? Are you actually reading a dated receipt? A mid-1991 date jives a lot more closely with the archived magazines. (The other item on your BOM that I'm wondering about is the 80MB hard drive. An 80MB drive looks like it had about a $200 price premium over a 40MB in September 1990, and that would have been more in May. Again, price adds up better if you add a year and change. You could probably get a 386sx for $1,350 in May 1990, possibly even with mono VGA instead of Hercules, but I'm thinking that's a 1/40MB config, not 4/80MB).



