Hi to all, I’ve tried to upgrade from: Module Make Micron Tech Module Size 256MB 2 row/4 banks Module Type unbuffered DDR SDRAM Module Speed PC2100 (133MHZ) Module Voltage SSTL 2.5 Error Correction ECC Highest CAS Latency 2.5 (7.5ns @ 133MRZ) I get 2 short and 1 long beep when I try to upgrade (won’t boot) using: Module Make Micron Tech Module Size 512MB 2 row/4 banks Module Type unbuffered DDR SDRAM Module Speed PC2100R (266MHZ) Module Voltage CL 2.5 Error Correction ECC REG Can I use the ECC REG stick or is there a bios problem (its set to enable ECC) ? ? ? ? Hoping this is not too confusing and any help in this matter is appreciated. This is my system: OS Name Microsoft Windows XP Professional Version 5.1.2600 Service Pack 2 Build 2600 OS Manufacturer Microsoft Corporation System Manufacturer Compaq (HP) System Model Evo W4000 workstation Processor x86 Family 15 Model 1 Stepping 2 GenuineIntel ~1794 Mhz BIOS Version Compaq 686Y2 v2.11 Physical Memory 256.50 MB

You can't mix ECC & non-ECC if that's what you're trying to do. "I get 2 short and 1 long beep when I try to upgrade" Is it possible that you knocked the video card loose when changing the RAM? http://bioscentral.com/beepcodes/co...

I suggest you go to Crucial.com and use thier Memory configurator to find out what memory is compatible. The total number of banks, the chip density, capacity per slot and total capacity are all factors. As well as ECC RAM. I don't know the difference, if any between ECC and Registered ECC. It appears you have both kinds. That said, if jam checked the error code for your board then he is most likely correct. Trying the RAM will not harm the system as long as it fits the slots.

Hi Jam & OtheHill, Thanks for the quick response. Jam, I'm not trying to mix the sticks, rather one stick is (PC2100 256mg 133mhz) and the other is (PC2100r 512 mg 266mhz) both are ECC. When I plug the 512 stick the computer won't boot. I have tried Crucial but they don't show ECC sticks for my EVO w4000 computer. I'm stuck !

"I'm not trying to mix the sticks, rather one stick is (PC2100 256mg 133mhz) and the other is (PC2100r 512 mg 266mhz) both are ECC" 1st of all, I see know reason why you can't "mix the sticks". They're both PC2100 ECC RAM. And don't let the 133mhz vs 266MHz confuse you...ALL PC2100 RAM runs at 133MHz. 266MHz is the effective speed due to DDR technology. "I have tried Crucial but they don't show ECC sticks for my EVO w4000 computer." They don't show any, but they do say this in the Q & A section: "Q: Does my computer support ECC memory? A: Yes. Your system supports ECC. You can put non-ECC modules into an ECC system, but be sure not to mix ECC and non-ECC modules within a system. Install the same type of modules that are already in your system." http://www.crucial.com/store/listpa...

Hi jam, I tried with just the (PC2100r ecc 512mg), the system won't boot and gives me 1 short and 2long beeps ????? Computer works OK with the 256 stick. Any other suggestions (I Hope)? Still stuck

Originally you said "I get 2 short and 1 long beep when I try to upgrade" Now you're saying "the system won't boot and gives me 1 short and 2long beeps" I posted the Compaq BIOS beep codes in response #1 1 long, 2 short = Video error. That's why I asked if you knocked the video card loose. 2 short, 1 long = Reseat RAM then retest; replace RAM if failure continues. You could try cleaning the contacts on the new 512MB stick, but it appears that it's either bad or incompatible with your board.