Archive for July 21st, 2006

21
Jul
06

Beware the VRM

Sometime this spring our research group acquired a rack of Compaq ES40 server machines for free courtesy of MIT’s reuse email list. During the last few months we’ve been working periodically on getting it set up for our purposes. This has included installing Debian GNU/Linux and getting two 30 amp plugs installed in the room where it sits. While this machine is pretty sweet (4 nodes; 4 Alpha processors/node), it does have some shortcomings. Most notably, it is very low on hard drive space: each node has only a 9GB hard drive. To remedy the storage problem, I had been thinking about putting together a fileserver on which we could mount each user’s /home directory over NFS. Toward that end, I recently acquired a Dell GX300 with a Pentium III 800 MHz processor for free from the MIT Equipment Exchange.

Since our “new” fileserver came with only a 15GB hard drive, I bought a new 80GB boot drive and two 160GB hard drives to serve as a RAID1 array. Given that the motherboard supports two processors, I figured I could upgrade the computer on the cheap by adding another processor. This turned out to be a little tricky because I had to make sure that the two processors would work together. The easiest way to do this is to make sure that the so-called sSpec number is the same on both processors. (See this link for useful information on the whole line of Intel processors.)  After locating the sSpec number on the existing processor, I located some other SL4BX processors on eBay and ended up buying one for ~$28. This was not the cheapest SL4BX I found but it was the only one that was guaranteed to have a heatsink compatible with my computer case, so it seemed like the best choice.

This morning, after receiving my new used SL4BX, I installed it only to find that it didn’t work. While both processors work individually, I got a strange error message about a voltage failure when I tried to use both at the same time. So, I consulted the online documentation only to find that, in order to use two processors, an additional component is needed: a voltage regulator module (VRM). I had noticed a strange-looking plug on the motherboard before and wondered what it was for. It’s for the VRM. Back to eBay.

I looked around for quite awhile simply trying to figure out what part I needed. This useful piece of information was conspicuously absent from the Dell online documentation. Gradually, it became clear that I needed Dell part number 7649D, which is apparently identical to part number 11GEF, which is the same as part number 05S2020A-4 from some company named Delta, which apparently made these parts for Dell. I called Dell Spare Parts and the guy confirmed that the part I needed was the 7649D. From looking at photos online I was able to convince myself that the 7649D is the same as the 05S2020A-4 and that the 11GEF is the same as the 05S2020A-4. In any case, after pricing the 7649D and 11GEF, I came to the disheartening conclusion that the VRM was going to cost at least as much as the processor. In fact some used equipment retailers were asking as much as $100 for this part. In the end, I lucked out and found an 11GEF for the “Buy it now” price of $17.95 + $8.60 shipping. Thus, I managed to get the VRM for about $1.50 less than the processor. Despite finding the VRM for a reasonable price, this upgrade turned out to not be as cheap as I had anticipated.

I should have the part on Monday or Tuesday and the moment of truth will present itself. I really hope that everything works, otherwise I will have wasted scarce research funds on a wild goose chase for old computer parts. However, if everything does work, I’ll have a pretty sweet server machine on the cheap: Dual Pentium III 800MHz, 512MB (Rambus) RAM, 80GB boot drive, 160GB RAID1 Array for ~$250. Acknowledgements: MIT Equipment Exchange (base machine), Microcenter (hard drives), eBay (SL4BX, 11GEF).

21
Jul
06

The future of the Pirates’ roster

The Pirates’ July 29th game against the San Francisco Giants is Sean Casey Bobblehead night. It’s ironic, then, that Sean Casey could be playing for the Giants and not the Pirates that day. As the trade deadline approaches, trade rumors are swirling and one of the rumors that appears most credible is that the Giants are looking to fill a gap at first – with Sean Casey. According to this article, if the Pirates aren’t able or willing to sign Casey to a contract extension before the trade deadline, then he will be traded, likely to the Giants.

While Casey is probably the most prominent Pirate ostensibly on the trading block, he’s certainly not the only one to be discussed in trade rumors. According to this article, the list includes Craig Wilson, Joe Randa, Jeromy Burnitz, Kip Wells, Salomon Torres, and Damaso Marte. I also saw a different article that mentioned that Roberto Hernandez would probably be traded to the Yankees. So, basically, everyone the Pirates signed in the offseason to one-year contracts could be gone by the end of July. Honestly, I wouldn’t be that sad to see any of these guys go, except for Torres, Casey, and, to some extent, Craig Wilson. However, if they traded both Casey and Wilson, it’s not clear to me who would play at first. Ryan Doumit? Jose Hernandez? The Pirates’ depth chart lists Casey, Wilson, and Eldred at first, but Eldred had season-ending surgery a little while ago, so, while they’re probably targeting him as their first baseman for next year, they need someone to play this year.
We’ll have to wait and see what happens, but it’s certain to be an interesting 10 days leading up to the trading deadline.




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