Corsair XMS3000 DDR Memory
This time we are going to take a look at Corsair's 256 MB SDRAM DIMM. PC2700 isn't going to last forever and for overclockers only the fastest products are acceptable. XMS stands for Xtreme Memory Speed so right after you see the name you are tuned to expect the top perfomance available today.
Xtreme Memory Speed
PC3000, XMS3000, DDR370 etc. Names making you crazy? Just to clarify these a bit here is a little table from where you can see the relation between DDR and PC markings. I'm not going to go any deeper about the terminology and technology because this information is quite easily available with Google etc.
|DDR rating||PC rating|
Just take the DDR number and multiply it with number eight and you'll get the PC rating and if you divide PC number by eight you'll get the DDR rating. XMS3000 is PC3000 memory so with the following system we get DDR370. That means the DDR rate is 370 MHz while signalling rate is half that, 185 MHz.
Even though there are some people that say heat spreaders doesn't do anything for the module but it sure does make it look nice.
- Capacity 256 Megabytes
- Contains 32M x 8 DDR SDRAMs with speed of 6 ns.
- Integrated aluminum heat spreaders at both sides
- Lifetime warranty
- Tested to work with 185 MHz at cas2
I tried and tried but wasn't able to pull those spreaders apart. They have used some kind of heat transfer tape that sticks really well. Red arrows indicate the chips under the spreaders. As you can see they are not aligned. This ensures even better cooling because there isn't any other chips heating the pcb from the opposite side.
Module is SPD programmed to pc2700 to comply with JEDEC. PC3000 isn't currently defined by this organisation. Modules are tested and quaranteed to reach 185 MHz with 2-3-3 1T and 166 MHz with 2-2-2 1T. All this with default DDR voltage that is 2.5 volts. Let see what my system can do with this module.
- AMD Athlon XP 1800+ unlocked
- 1530 MHz
- Soyo KT333 dragon Ultra platinum edition
- Albatron Geforce4 Ti4400
- Samsung SV4002 40GB ATA100 5400rpm
- Hec 300LR 300W
Operating system and drivers
- Windows XP pro
- VIA 4-in-1 4.42
- NVidia DetonatorXP 30.82
My Soyo Dragon Ultra was unable to work with FSB speeds higher than 165 MHz so I had to use async mode for the test. While this gives slightly lower benchmark results it will still run the memory with the indicated MHz speed and that is the information that we really want.
SiSoft Sandra 2002 Memory Bandwidth Integer
RAM Int buffered
SiSoft Sandra 2002 Memory Bandwidth Float
RAM Float buffered
I wanted to use Kingston's pc2700 memory module for comparison but the highest speed that it was able to handle was 178 MHz even with 2.5-3-3. At the stock speeds the modules performed similar but when the signalling rate goes up Kingston falls.
I tested the modules with 166 MHz with different CAS settings so you could get a feeling how much it affects the performance of the module. Also the command rate affects the performance quite a lot and it is clearly visible on the results.
I was able to run Sandra's tests many times with speed of 185 MHz and 2-2-2 1T. DDR voltage was 2.5 which is the default value. As you see the module delivers what it promises. I then rised the voltage to 2.7 volts and loosened the settings and was able to run the module with speed of 195 MHz. Don't think that this is the best than this module can do because I've seen results far over 200 MHz. There has been some talks about USB 2.0 chip not being able to handle high FSB speeds with this motherboard so maybe this was the reason why it wasn't able to go any futher.
What can I say? It's black, extremely fast and has a lifetime warranty. It's hard to find anything bad to say about this module so it really deserves the first editor's choice given out by me.
I would also like to thank Jimm's PC Store for supplying the silver paint for unlocking the processor.
Pros and Cons