2-2-2-5 or 2-3-2-6?! confused here...

[Lancelot]

My old ValueRAM could only do 2.5-3-3-6 @DDR400 but now I got some HyperX I started reading up on tight memory timings and I've been getting confused! My new HyperX memory is spec'ed 2-2-2-6-1T (the good BH5 stuff) but ofcourse @DDR400 it runs 2-2-2-5 without a problem. However when you read up on memory settings/timings and such, you'll find that offcially TRC should always be set to the value of TCAS+TRAS+2 (2-2-2-6 or 2-3-3-7) and it even says that running TRC too low could cause a performance hit under some conditions!? And then i865/875 don't support a TCAS of 2 so officially the best timings supported by the chipset are 2-3-2-6?! I see most of peeps with performance RAM running 2-2-2-5 anyways, so what are your thoughts on this?

[Speed_Mechanic2]

You should be able to run tCL of 2.0, tRCD of 2, tRP of 2, tRAS of 6 (2-2-2-6) on i875/i865 motherboards with BH-5 memory. Try raising the VDIMM to 2.7V or 2.8V.

[stan03]

yea actually on my mobo depending on the timings i run, i actually sometimes get a higher bandwith at less tight timings :eh?:

[larva]

My highest scores occur at 2-2-2-5, so just try both and see. I haven't had to even run x-3-x-x, but I have plenty of voltage on tap. The volt mod for you board is very easy and will allow tighter timings if used to provide the memory with 3-3.1V. My latest PCMark2002 memory test (running 2-2-2-5/380MHz on 2.97V) was 10,711, it drops off any other values. 3DMark2001, Quake3, and SETI, and stability testing show 2-2-2-5 to be best for my rig. Try yours.

[Lancelot]

Thanks Larva, then I'll stay at 2-2-2-5. It's been running both SETI and Prime95 overnight like this (9+ hours) and I'm noticing that SETI WU's average 2:50-2:55 hours now compared to 3:10-3:15 with my old ValueRAM. I don't think that Volt-mod is something for me cuz my CPU is hitting a wall around 255FSB and this RAM won't do DDR500 whatsoever so I like staying at 5:4 DDR400 with the fastest timings.