What FSB/timing is PC4000 maxing at?

OK, I know someone must be pushing the limits on PC4000, so who is at 265+ FSB with 1:1 ratio and decent timings? What brand are you using?

I just got back in the game after about a year and replaced a 2.53/845PE setup with what's in the sig. I had 2x256 sticks of XMS 3200C2PT, so I just opted to stick them in the mobo for the time being, but they're at their limit for sure. 430 DDR 2-2-2-5 is the max I've run them, but toned it all down a notch for my own sanity (3450MHz/424DDR 2-2-2-5) WITH the turbo option in the BIOS on (woohoo!)...all on air.

I must say I am pretty happy with the OC of the whole thing, but can't help thinking what my mem scores would be like if I had PC4000 running 1:1 instead of the 5:4 the 3200 is stuck at Since that would be DDR 530 at my current "daily" OC, is anyone seeing that kind of speed or higher out of PC4000? If so, could you please let me know the brand (I am partial to Corsair XMS and what kind of timings you are running?

FYI, for the 3200 2-2-2-5 @ 265FSB, the best PCMark2002 mem score that I've had so far is 107xx and ~5920MB/s in SandraMAX.

I appreciate any info you can pass along...

seems like the 875 chipset is designed to operate at very high fsb(250 and above at 1-1). tight timings dont seem to be as much an issue as with the older intel chipsets and the amd chipsets....

Tight timings are still important on i865/i875 boards. Bandwidth improves, of course, with higher FSB clock speeds, but performance in 'real-world' tests (gaming, ect.) don't show the gains.

The best timings I've seen with 4ns DDR500 is 3-3-3 (2.5-3-4 is just wrong). However I havn't heard of many, if any, users getting above 260MHz with tRCD-tRP of 3-3, having to resort to a timing of 3-4-4. Running tRCD-tRP of 4-4 really hampers the gains by increased clock speeds.

Look at it like this:
With 4ns chips, it takes 4ns to perform a cycle (CK). With timings set at 3-3-3 (CK - cycles), then timings are 12-12-12 (ns). This is 20% longer then 5ns chips running at 2-2-2 (CK) or 10-10-10 (ns). Running at 3-4-4, however, increases the differance to 60%, 16-16-16 (ns) compared with 10-10-10 (ns). Memory using Hynix 4.3ns chips are worse, with timings of 3-4-4 commands are run 72% slower then 5ns chips at 2-2-2. With differances of 72%, you will need to have a serious clock speed advantage to equal out the performance.

With your Corsair memory running at 215MHz at 2-2-2 5:4 your performance will be about the same as memory running at 265MHz 1:1 with timings of 3-3-3. Something not worth the high costs of DDR500. If you are forced to use timings of 3-4-4 with DDR500, then your performance may be actually lacking compared with your current set-up.