PC Troubles
Posted on 18/08/07 16:24
Fortunately it's up and running again now, but I thought I'd frazzled my PC at home.
Last week I was round at Steve and Ally's place, and Steve had a couple of matched pair of Corsair TwinX 1024 MB sticks left over after upgrading his machine. Having been thinking about upgrading the RAM in my machine (photo editing consumes lots of RAM), I bought them off him to save him sticking them on eBay. Today I put them in the machine, and following his advice, manually configured the BIOS settings as by default they are detected as having a CAS latency of 3, even though they are sold as CAS 2. Alas, that was the last time the machine would even get as far a the POST.
Much cursing and swearing later, consulting Corsair's website, MSI's website, various forums, and the manual for my K8N Diamond motherboard, I remembered that there's a set of diagnostic LEDs that give you a clue what's going on during the boot sequence. The conclusion I came too was that the BIOS couldn't decompress to the RAM, and then I recalled you can probably reset the RAM with a jumper on the motherboard. Turns it it's a switch, which made life easier, and hey presto, the PC fires up and POSTs again.
Re-reading the info on the Corsair site, it turns out that the CAS latency should be set to 2.5 (and not 2) for AMD systems. This done, and hey presto it restarts fine. The info from Corsair is reproduced below (as there's no direct link available):
On another note, my next door neighbours Paul and Margaret asked me to have a look at their PC as it stopped working. Turns out the hard drive had failed, and I've had much more success in replacing that an re-installing WinXP home. Unfortunately I had to talk to Microsoft (for activation) and managed not to fail the trick quesion "how many PCs is this software installed on?"
Anyway, I'm now off to see if my new, improved memory makes my photo editing software work any better.
Last week I was round at Steve and Ally's place, and Steve had a couple of matched pair of Corsair TwinX 1024 MB sticks left over after upgrading his machine. Having been thinking about upgrading the RAM in my machine (photo editing consumes lots of RAM), I bought them off him to save him sticking them on eBay. Today I put them in the machine, and following his advice, manually configured the BIOS settings as by default they are detected as having a CAS latency of 3, even though they are sold as CAS 2. Alas, that was the last time the machine would even get as far a the POST.
Much cursing and swearing later, consulting Corsair's website, MSI's website, various forums, and the manual for my K8N Diamond motherboard, I remembered that there's a set of diagnostic LEDs that give you a clue what's going on during the boot sequence. The conclusion I came too was that the BIOS couldn't decompress to the RAM, and then I recalled you can probably reset the RAM with a jumper on the motherboard. Turns it it's a switch, which made life easier, and hey presto, the PC fires up and POSTs again.
Re-reading the info on the Corsair site, it turns out that the CAS latency should be set to 2.5 (and not 2) for AMD systems. This done, and hey presto it restarts fine. The info from Corsair is reproduced below (as there's no direct link available):
Why are the timings shown in the SPD set to CAS 3?In my travels, I also dicovered that 2-3-3-6 refers to CAS-tRCD-tRP-tRAS. It's still mostly greek to me (not much of a geek am I?) There's some (possibly questionable - see editors note) info on the CAS latency Wikipedia page.
All of our XMS-3200C2 will have their SPD set to JEDEC defined values for the specific memory IC used to make that part. This is done to ensure maximum compatibility with a wide variety of motherboards. The tested settings Cass 2-3-3-6 for Intel and Cass 2.5-3-3-6 for AMD need to be manually set in the BIOS.
On another note, my next door neighbours Paul and Margaret asked me to have a look at their PC as it stopped working. Turns out the hard drive had failed, and I've had much more success in replacing that an re-installing WinXP home. Unfortunately I had to talk to Microsoft (for activation) and managed not to fail the trick quesion "how many PCs is this software installed on?"
Anyway, I'm now off to see if my new, improved memory makes my photo editing software work any better.
