When should you lower the HTT to 4x?

[chefwaffles]

how high can you raise the FSB on HTT 5x before having to lower it down one to become stable?

[iboomalot]

that varies but over 225 I would lower it

[Vapor]

When it breaks 1100HTT (FSBxLDT) is when I drop it.

[uOpt]

People report failures right over 1000 MHz Hypertransport, so any overclock should have the multiplier below 5x.

Note that DFI boards in the "auto" setting do that automatically.

[pancake]

my optie 146 was benching happily at 4 x 300 fsb ( 1200) , until i noticed and dropped it to x3 trying to get 3.1 stable

[taurus_sel]

Depends on the chipset. nvidia's chipsets are notorious for having little to no margin on the HT bus over 1GHz. Remember back in K7 days they couldn't even run the spec'd 800 MHz HTT and had to fall back to 600 MHz. Then when K8 came around they couldn't initially ship the NF4 because of major yield problems at 1GHz. They've always been crappy at HT overclocking. Even their latest chipsets C19 and SLIx32 are the same. On the other hand,
ATI's current chipsets are a lot better and routinely do 1.2GHz and above. According to Anandtech, their next chipset the RD580 will do over 1.5GHz (300HTTx5) without a problem.

[mdzcpa]

Depends on the chipset. nvidia's chipsets are notorious for having little to no margin on the HT bus over 1GHz. Remember back in K7 days they couldn't even run the spec'd 800 MHz HTT and had to fall back to 600 MHz. Then when K8 came around they couldn't initially ship the NF4 because of major yield problems at 1GHz. They've always been crappy at HT overclocking. Even their latest chipsets C19 and SLIx32 are the same.

I have to disagree. I've had three recently purchased NF4 mobos all of which run 240-250 x 5 (1200 to 1250). Both of my Expert boards can do it right now. The newer steppings are running much higher HT limits.

[taurus_sel]

I've tried 2 A8N-SLIs and a DFI NF4 Lanparty UT and both failed at 1.1GHz. So I haven't seen the same results as you. This is overvoltaged to 1.4V.

I have to disagree. I've had three recently purchased NF4 mobos all of which run 240-250 x 5 (1200 to 1250). Both of my Expert boards can do it right now. The newer steppings are running much higher HT limits.

[mdzcpa]

I've tried 2 A8N-SLIs and a DFI NF4 Lanparty UT and both failed at 1.1GHz. So I haven't seen the same results as you. This is overvoltaged to 1.4V.

Fair enough. I can certainly understand that you've had less than steller results personally. I had similar results with the older batches of NF4 boards as well....not too mention the Asus NF4s aren't the top clockers to begin with.

However, recently things have been much improved. This is why I commented on your generalization.

I just ran this:
http://www.xtremesystems.org/forums/attachment.php?attachmentid=40737&stc=1&d=1133737659

Actually this particular board can run even higher. The above was done with stock chipset and HT voltage too:)

[Shinuza]

Ability to boot over ~1.1ghz is depending to :

Number of devices connected to the MCP
Number of devices actived in the MCP (sound, LAN, ect)
Dual mode actived or not
LDT voltage
Chipset voltage
Chipset temperature
LDT/BUS Transfer width

300x4 should works with no problem.

[taurus_sel]

Cool. Understood. Don't want to stir up anything but SuperPi stability doesn't stress HT link at all. The only thing that can really stress the HT link is a high end graphics card using extensive amounts of system memory or very high bandwidth peripherals.

Fair enough. I can certainly understand that you've had less than steller results personally. I had similar results with the older batches of NF4 boards as well....not too mention the Asus NF4s aren't the top clockers to begin with.

However, recently things have been much improved. This is why I commented on your generalization.

I just ran this:
http://www.xtremesystems.org/forums/attachment.php?attachmentid=40737&stc=1&d=1133737659

Actually this particular board can run even higher. The above was done with stock chipset and HT voltage too:)

[shoman24v]

But you don't want to be clocked at 2.8GHz but have your HTT at like 750MHz right?

Would your computer technically be 2.8GHz or less since your HTT isn't at 1GHz?

[mdzcpa]

Don't want to stir up anything but SuperPi stability doesn't stress HT link at all. The only thing that can really stress the HT link is a high end graphics card using extensive amounts of system memory or very high bandwidth peripherals.

LOL...you're not stirring anything up. What I showed above is completely stable for hours of gaming with my 7800GTX 512 cars in SLI. I can also rip and encode, play on line games, and do everything else at these speeds. The pic above was just to show you my DAILY HT speeds:D

EDIT: How's this? This might be stressing the HT bus...maybe a little anyway:D

http://www.xtremesystems.org/forums/attachment.php?attachmentid=40738&stc=1&d=1133741489


Anyway, like it was stated above, it does depend on how your system is configured. I have all the bells and whistles running on this particular system and I can still run 250 x 5 all day long. My other Expert can do it too. It tells me the newer boards are doing much better HT wise.

[uOpt]

But you don't want to be clocked at 2.8GHz but have your HTT at like 750MHz right?

Would your computer technically be 2.8GHz or less since your HTT isn't at 1GHz?

AMD's Hypertransport bandwidth is vast overkill. You won't be able to measure an actual performance difference between 800 or 1000 MHz. CPU and memory speed are not affected.

You can try for yourself at the same CPU speed.

[taurus_sel]

Cool. Actually looking at your set up I see an FX57 (E4 die). The CPUs have actually improved quite a bit as well. It would be interesting to see a rev CG die. I was using a rev CG FX55 and an E6 die dual core. The rev CG could barely break 1GHz. The E6 die was around 100 MHz better.

LOL...you're not stirring anything up. What I showed above is completely stable for hours of gaming with my 7800GTX 512 cars in SLI. I can also rip and encode, play on line games, and do everything else at these speeds. The pic above was just to show you my DAILY HT speeds:D

EDIT: How's this? This might be stressing the HT bus...maybe a little anyway:D

http://www.xtremesystems.org/forums/attachment.php?attachmentid=40738&stc=1&d=1133741489


Anyway, like it was stated above, it does depend on how your system is configured. I have all the bells and whistles running on this particular system and I can still run 250 x 5 all day long. My other Expert can do it too. It tells me the newer boards are doing much better HT wise.

[ozzimark]

Depends on the chipset. nvidia's chipsets are notorious for having little to no margin on the HT bus over 1GHz. Remember back in K7 days they couldn't even run the spec'd 800 MHz HTT and had to fall back to 600 MHz.
come again? K7 boards had an HT link? ;)

[Serge84]

Well my htt is 1400, 2800MT/s with no problems. Totaly depends on the board. My onbord gpu is dependent on this alot. I bench 8000 on 3Dmark at a htt of 4x 350fsb. You know how fast that is. And if I turn it to 1x 350fsb it will bench at 4000 or lower. Thats why its so good for my system. And depends how you use it. If its used much. So actouly you will tell a diff, just depends what you use it for.

[Serge84]

Depends on the chipset. nvidia's chipsets are notorious for having little to no margin on the HT bus over 1GHz. Remember back in K7 days they couldn't even run the spec'd 800 MHz HTT and had to fall back to 600 MHz. Then when K8 came around they couldn't initially ship the NF4 because of major yield problems at 1GHz. They've always been crappy at HT overclocking. Even their latest chipsets C19 and SLIx32 are the same. On the other hand,
ATI's current chipsets are a lot better and routinely do 1.2GHz and above. According to Anandtech, their next chipset the RD580 will do over 1.5GHz (300HTTx5) without a problem.

Oh really, my NF4 Geforce6100 is loveing this HTT OC. Look at my benchmarks of sandra she doesn't lie. I bet I could go over 3000MT/s if my CPU wasn't limited to this 350fsb.

[Ic3man]

With the new A8n32 :

http://img.photobucket.com/albums/v608/webbo10/HTT.jpg

:cool: