Rambus PC figures give that FUD feeling
Time for a new RegMark™
Letter Following an article we published yesterday in which we mentioned that Rambus has posted figures showing that its RIMMs do not need to be more expensive than synchronous memory, a reader (email address supplied) has sent us the following letter: Sorry if I keep writing about nitpicky techie things, but I noticed another one today. The Rambus figures [on its Web site] quote a machine equipped with RDRAM as being only marginally more expensive than a SDRAM machine, and they are right, it can be. You'll notice that they say nothing about the performance of these machines in relation to RDRAM. The subtleties are astounding. You can combine the numbers to say RDRAM can be faster or not much more expensive than SDRAM. Yup. Not both though. Here are the numbers that I hastily dug up, along with links.
Please note how the PC600 is closer to PC500 than PC525, much less PC600. Heh. The above pricing data was taken from Gigabuys. If it doesn't link, go to the Dell main page, then Gigabuys, then search for "RIMM"). The pricing is current as of the time of this e-mail.
The bandwidth figures are taken from a Tom's Hardware Guide article called "Showdown at 133 MHz FSB - Part2, The Real McCoy", specifically which can be found here.
For SDRAM, if you again go to Gigabuys, and search for SDRAM, filter by ECC and Kingston Technology (the makers of the above quoted RIMMS), you get the following: 128Mb ECC SDRAM DIMM $272.95 (Intellistation RAM. I am using one now, generic works here, and vice versa. In fact I am using the exact model quoted, the M Pro 6889) 256Mb ECC Registered SDRAM DIMM $564.95. I could not find PC133 RAM on Dell's site (gosh, wonder why?), so I will use the "cheaper" PC100 instead.
OK, enough of the hard numbers. Basically, your Monday article used PC700 RDRAM (at least I am pretty sure that is what the 700 in T700r means). For the sake of sheer number juggling, lets use PC600 RDRAM for comparison purposes. If you take a machine equipped with 64MB of PC600 RDRAM, the memory alone will cost you about $304.50, half the 128MB RIMM price above. The 256MB is almost exactly twice the cost of a 128MB, so you do the maths on the 64MB). Using the same logic, 64MB of SDRAM would cost about $136.50, or almost exactly the same as the $161 quoted in your article. Basically, the math of the Rambus PR bunnies seems correct, but their logic is questionable at best. We basically proved here that Rambus can be merely twice the cost of PC100 SDRAM.
Now onto the logic bit. But first, some more prices. All the prices are taken from Chip Merchant. Not that they are a very good, or even cheap site, but they are a name, I have used them, and they do deliver, and answer the phone if you call with a problem. Basically, a representative, average web merchant price. You could do better on Pricewatch, but I don't care enough to look right now. Here is what I got: PC100 DIMM, 128MB $116 PC100 DIMM, 256MB $231 PC133 DIMM, 128MB $123 PC133 DIMM, 256MB $264
You'll note here that PC133 is about one fifth of the cost of PC600 RDRAM, and one sixth the cost of PC800. If you look at the performance numbers in the Tom's article listed above (about five screens after the one listed), you sill see the following patterns emerge: On office applications, PC600 is thoroughly abused by everything, including the pathetic i820+MTH, the laughing stock of... well, everything. The performance is laughable. On rare occasions, it beats PC133, but for the most part is is a joke. An expensive joke though. PC700 and PC800 are notably better on every occasion.
Please note that all the comparisons here are on the same (i820) chipset. For games and 'professional' graphics apps, RDRAM does much better, equaling the performance of PC133 on the Via chipset. Either way, for about 90 per cent of applications, RDRAM in any speed is no better than PC133, and in some cases much worse. Now back to the original point. You can make Rambus cost a little more than a comparably equipped SDRAM PC, if you use almost no memory, and pick the slowest type of RDRAM possible. Performance will suffer, and you will end up with a barely useable ($3000 PIII/800 64MB) machine, but again, it can be done. Using only CPU and memory prices, the most sane would pick a PIII/866 with 256MB PC133 ($909+$264=$1173) over a PIII/700 with 128MB PC800 ($426+$759=$1185) any day of the week
Any guesses as to why no one posts reviews based on overall machine cost, or at least cost of those two components? I sense a new Regmark™ in the making. If I could get my hands on the parts, I would run the benchmarks for you, but alas I am broke and can't afford anything near that much money. *SIGH*. If you have any pull with hardware sites, pass the speed per $ test to them, and see what they come up with, and ask a Rambus spokesdrone about it also. Bet you won't get an answer to the question. The processor prices were taken from JC's site. Hope this helps explain the numbers game Rambus is pulling. It is always fun to watch the press releases from companies without a technical leg to stand on. Great fun too. ®