E8400 + 780i @ 4175Mhz on air

[DerekOldschool]

After getting my little old e2150 to go from 1.8Ghz to 3.46Ghz I had to get my hands on one of the new 45nm CPUs and I wasn't disappointed. Yeah, I had to jam 1.5v to get it stable, but my temps are ~30C idle and under load they generally stay in the high fifties but will get up to low sixties when running Orthos with small ffts.

One thing to note was that my 3d06 score went from ~14100 with the e2150@3.46Ghz to the 19139 score you see in the screenshot with the e8400

[sswilson]

Cool!!!

Is this a newer E8400? I just dropped on into my system and I've got it stable @ 4250 under water, but that took 1.475. Seems like the newer batches of E8400s are taking higher V to get them up over 4g. Only time will tell what 1.4+ Vcore will do to them.

Great to see your score jump like that with the CPU change. I went from a high OC'd quad so my scores dropped from mid 1600s to mid 1500s, but that's a reflection of high CPU scores rather than actual GFX crunching... my GFX #s actually went up.

That 9800X2 really shines!!! :)

[DerekOldschool]

It's gotta be one of the newer ones - packing date on the box is April 10/08 - SLAPL stepping or batch

I found the 9800GX2 is not that much faster than the 2 8800GTS 640M I had (newer drivers seem to be fixing this) I was lucky to get it because eVGA extended their step up program to 120 days on the card - which made one of the 8800s eligible for the step up. Otherwise I would have had a hard time coming up with an excuse to shell out $600 in one shot. As it was I paid ~$350 for the 8800 (and got a free copy of Crysis with it that I got to keep!) and then almost 4 mos later forked out the balance of about $250. This also freed up the first 8800 so that it could be put in my "guest gaming system" - the FireryPheonix rig in my sig

[3oh6]

@ OP, nice work with the 780i, ima 790i man myself and absolutely loving the NVIDIA boards.

Originally Posted by sswilson

Seems like the newer batches of E8400s are taking higher V to get them up over 4g. Only time will tell what 1.4+ Vcore will do to them.

no blanket statements allowed when it comes to overclocking

every batch of CPUs has the ability to be completely different than the last or the future ones. the silicon will vary greatly and the characteristics will too. i have recently tested a handful of Q808As and Q810As and the differences between them is night and day. the Q808As run hotter than the sun having a tantrum and the Q810As don't. the overclocking is obviously a lot different as well with the Q808As out pacing the Q810As drastically in all cases.

with that said, the Q808As showed a fairly large overclocking range amongst themselves. so even the same week/batch isn't going to clock alike.

here is the best Q808A476 i ended up with...and it is a complete monster. a quick prime run at 4250MHz...notice the vCORE in CPU-Z, it is bang on to a DMM reading. it is being cooled by a Thermalright Ultra-120 in about 23C ambients. it runs toasty hot, even at this low vCORE:



and of course a wee bit higher for single 32M stability :D



the worst Q808A was a good bit behind this one but closer to the average of the rest. this one was just a one off freak of freaks. it is being put to good use though so it won't go wasted in some un suspecting fool running it at stock :D

[DerekOldschool]

Another thing I noticed about this CPU is that I was able to run it at about the same speed with an 8x multiplier (~520 x 8) but the read score on my memory bandwidth test went down by ~10%.

I figured that with the higher FSB speed the memory bandwidth would go up because thats what happened with the e2150

Needless to say I went back to the x9 multi - but the board has a fsb hole at ~466 x 9 = ~4200Mhz, so I was trying to get around it. However, it seems that my cpu's limit is about 4.18Ghz @ 1.5V and I don't plan on giving it any more juice.

[sswilson]

Originally Posted by DerekOldschool

Another thing I noticed about this CPU is that I was able to run it at about the same speed with an 8x multiplier (~520 x 8) but the read score on my memory bandwidth test went down by ~10%.

I figured that with the higher FSB speed the memory bandwidth would go up because thats what happened with the e2150

Needless to say I went back to the x9 multi - but the board has a fsb hole at ~466 x 9 = ~4200Mhz, so I was trying to get around it. However, it seems that my cpu's limit is about 4.18Ghz @ 1.5V and I don't plan on giving it any more juice.

Thanks for the heads up. I was shooting for highest stable FSB (Thinking that it would give me the best performance) so settled on 500fsb X 8.5 with mem at 1:1. Now that I've got that stable I'll have to try out the 9X performance at a lower FSB.

[3oh6]

Originally Posted by DerekOldschool

Another thing I noticed about this CPU is that I was able to run it at about the same speed with an 8x multiplier (~520 x 8) but the read score on my memory bandwidth test went down by ~10%.

that won't have anything to do with the CPU...it should be something with the MB. with the 790i, there are two options in the BIOS, P1/P2. when set to AUTO, they stay enabled up to 450~475FSB depending on CPU. after that though, they are disabled and drastically reduce bandwidth because they are responsible for chipset latency timings. enabling P1/P2 manually allows the chipset to maintain the same latencies and bandwidth scales with FSB accordingly.

not sure if there is similar settings for the 780i or not but thats what it sounds like to me. similar to the old chipset strap change of 401FSB on P965 boards.