unsigned long geek = random();

After sending this information to various mailing lists over the last few months, I thought I’d add it here for those who don’t rely on the LazyWeb…

The Sun Ultra 5 and Ultra 10 are almost identical. They share the same motherboard, only the PCI backplane and case differ. Unlike most Sun machines of that vintage, they take fairly standard RAM – 168-pin 3.3V ECC EDO DIMMs, common in x86 servers of the time. The motherboard has four slots, but due to the size of the Ultra 5′s case it can typically not take 256MiB DIMMs – unless they’re half height or staggered DIMMs, they won’t fit. Although the Ultra 5 officially supports a maximum of 512MiB RAM, 4x256MiB DIMMs will work fine if they’ll fit.

My one Ultra 5 has 4x128M Compaq DIMMs, bought on eBay for $38, and they work fine (the machine has been rock solid since I added the RAM).

For reference, the RAM is Compaq part number 169234-002, supported by the following servers:

• Proliant 4000
• Proliant 5000
• Proliant 6000 6/200, Model 1
• Proliant 6000 Xeon 6/400, 6/450, and 6/500, Model 1/2S
• Proliant 6500r
• Proliant 7000 6/200 Models 1S/2S
• Proliant 7000 Xeon 6/400, 6/450, and 6/500 Models 1, 1S, 2S