SDRAM Sources

ED Note: I received this email and thought the sources listed would be of interest – Joe.

How do those ctSPD memory timing settings and what FSB a memory can boot up at, relate in terms of memory performance? Does it improve memory bandwidth scores or just allow for better stability at higher speeds? Most people are used to just seeing Sandra and 3DMark scores, but I’m curious to know if using ctSPD can get an indication of how well a stick will overclock or if it can really do Cas2 at 160Mhz, as some companies claim.

Its very hard to tell if it’s the memory letting you down, or something else sometimes. As you say, you need to experiment on your own system, to see if running a higher FSB is better than running at fastest memory settings but slower FSB. I also notice that CPUReview have a little memory benchmark utility they are testing called MemTach.

I’ve been looking at high speed SDRAM to go with an Iwill KK266 and the high speed memory market has become quite confusing. This look at how many different types are ‘supposed’ to run Cas2 at high speeds:

OCZ Performance Series Max PC175
OCZ Performance Series Pro PC160
OCZ MicroBGA PC166
Tonicom PC166
SyncMAX VC PC166
Memman PC166
PQI PC166
TwinMOS PC166

Corsair PC150 Cas2
Mushkin PC150 HSDRAM
EMS PC150 HSDRAM
Kingmax TinyBGA PC150
Apacer WBGA PC150

Crucial PC133 Cas2
Memman VC PC133
Mushkin High Performance Rev3

A lot more than I was expecting; surely one or two must be better than the rest? There are mixed responses for many of these. Especially the PC166 ones, where some claim it works fine with Cas2 at 166, others claim it’s really only Cas3 at 166Mhz. Maybe ctSPD could prove or disprove this.

Some say you need to increase the I/O voltage to get it to run at higher speeds if you are having trouble. I had heard good things of Tonicom PC166 and when I heard that OCZ were going to use the same MicroBGA memory chips in their PC166 I was looking forward to your review.

Then I was disappointed at what you had found. Strange because Tonicom PC166 was used by Icrontic.com and OCworkbench.com with a KT7A board and got up to 183MHz, but with the slowest memory settings and disabling some settings in the BIOS. Maybe they had to raise the VIO.

Someone on a forum suggested there are both Cas2 and Cas3 versions of Tonicom PC166 and you have to be careful which one you get. At least some resellers on Pricewatch.com now list it as Cas3 memory instead of Cas2.

I also noticed Mosel Vitelic do some SDRAM chips that run at 166/183/200 Cas3, but don’t know if they are used on any SDRAM modules yet. SyncMax VC PC166 looks interesting, since VC memory is supposed to perform better as long as the motherboard supports VC memory, although I don’t think VC memory supports 4-way interleaving. Although some people said SyncMax VC PC166 was really PC133, Cas2.

Nitestorm