FM2+ Chipsets

[Daveburt714]

I'm getting ready to upgrade my HTPC. I'm going with an FM2+ board so it will be ready for Kaveri in a few months.

Do the A88 chipsets offer any advantage over the A75's? I've tried googling it and can't find any info on the differences...
I purchased parts yesterday, including an Asus A88XM-A http://www.microcenter.com/product/4...MD_Motherboard
After starting the build I realized this board only has one (1) on-board fan header (other than the CPU header).
This just won't do for my build...

MicroCenter has a limited selection of mATX FM2+ boards and the only other one I saw that would meet my needs is the ASRock FM2A75M Pro 4+:
http://www.microcenter.com/product/4...MD_Motherboard

Does anyone know if/what drawbacks the older A75 chpset might have with Kaveri?

I'm not worried about overclocking this build, so if it's just a matter of more I/O on the A88 I'll go with the ASrock.
It has more than enough I/O for my needs in an HTPC....

Thanks,
Dave

[AlleyViper]

You can always add something like this, if you really don't want to use a fan controller.

[Daveburt714]

Thanks AlleyViper ...

As long as I've been messing with computers I've never seen those. Too bad I already took the board back and swapped it out for the ASRock Pro 4+...
I'll definitely keep that cable in mind for future builds though!

Since my (impatient) self couldn't wait for a reply before retuning the A88 board, I'm still curious about the differences between chipsets w/Kaveri.
I realize Kaveri isn't out to the general public yet, but I was hoping some of the guru's who get advanced access to new AMD products might chime in...

The Stilt, Flank3r, I know both you guys get beta testing rights on new AMD gear.
As long as the question doesn't violate NDA would either one of you care to offer some insight?

[The Stilt]

The A88X chipset offers nothing new compared to A85X.
In fact it is worse than it's predecessor.

A88X has an upgraded AHCI / RAID controller which makes it unable (as it currently appears) to run over 106MHz BCLK while AHCI is enabled. Personally I would rather see the top tier FM2+ motherboard using A85X FCH instead of the A88X.

[chinook]

That's a shame.. I want to buy the Asus A88X-PRO and get the top kaveri model at launch. This board is nowhere to be found in Romania... Now, i'm not so sure which board would be best for overclocking and still retain some good features. I followed your comments, The Stilt and compared it with Asus A85-V Pro and found little differences (PCIE 3.0, onboard audio, some software, debug codes, -1 sata port, +1 esata port).
Do you have any info if they're gonna solve the controller impeding BCLK issue?

[justapost]

A88X has an upgraded AHCI / RAID controller which makes it unable (as it currently appears) to run over 106MHz BCLK while AHCI is enabled. Personally I would rather see the top tier FM2+ motherboard using A85X FCH instead of the A88X.

Amd added an internal clock generator to there 800 chipset as an option. Can be it is still possible to use an external clock generator on A88X to detach it from BCLK but that option is no longer used.

[The Stilt]

The internal clockgen(s) has existed since SB600.
The issue is not about internal clockgen being used but the AHCI/RAID controller itself.
It always operates at the BCLK frequency no matter if the CLKIN frequency is sourced from a external or one of the internal clockgens. The FCH cannot use multiple clockgens simultaneously it is either the external or one of the internals.

It was the same for Ax5(X) series chipsets, however the AHCI/RAID controller in Ax5(X) could withstand up to 140MHz BCLK.

The internal clockgens found in Jaguar and newer SoCs is much more smarter.
All of the different frequencies can be adjusted separately in relation to BCLK (PCI-E, DISPCLK, SATA, USB, etc).

[justapost]

Just found old specs of an ICS951464 used on 690G here. Looking at the old spec this chip could generate five different frequencies called CPU/HTT/SRC/ATIG/USB via independant multipliers and dividers based on an 14.318MHz input from an crystal oscilator. I only played with the CPU multipliers and dividers back then but always had the impression SRC was used for SATA and at least back then was thereby independant of CPU ie. ref-HT/BCLK. I have no specs of the internal clock gens but expected that an external one may provide more flexibility.

[AlleyViper]

OT: that unfortunate situation reminds me of the first days of socket 754 on a Via KT800 exactly 10 years ago (no pci/agp lock).

[justapost]

While searching the web i found the "AMD A45/A50M/A55E Fusion Controller Hub Register Reference Guide". At least with the internal clock generator of that chip it was possible to select eighter the oscilator or CP_PLL_REFCLK (BCLK) as the clock source for sata.
Update: just realized these are all mobile chipsets. guess all soc's.

[Daveburt714]

Thanks for the info on the chipsets folks!
I had a feeling the newer variants only offered more in respect to I/O and this build isn't intended for OC'ing...

Just for the record, the ASRock (A75) Pro4+ is running very smoothly with the 5800k.
Hopefully I won't be in for any surprises when I drop a Kaveri chip in it (stock)...

Times are slow for AMD, but I always know where to come when I need answers from knowledgeable people!

Thanks Again,
Dave

[Himo5]

That's a shame.. I want to buy the Asus A88X-PRO and get the top kaveri model at launch. This board is nowhere to be found in Romania... Now, i'm not so sure which board would be best for overclocking and still retain some good features. I followed your comments, The Stilt and compared it with Asus A85-V Pro and found little differences (PCIE 3.0, onboard audio, some software, debug codes, -1 sata port, +1 esata port).
Do you have any info if they're gonna solve the controller impeding BCLK issue?

If you're still considering the A88X-PRO then whatever the chipset's disadvantage against the A85X I have to say the Asus A88X-PRO is a marked improvement over the Asus F2A85X-PRO.

This may just be down to the improvements in the BIOS and AI Suite, but there is also an enhanced VRM setup with huge heatsinks that gives a feeling of power and stability to the installation process and the way it runs that wasn't there before - even with My F2A85X-PRO.

Trying an A10-6800K APU with 16Gb of Trident-X 2400MHz RAM straight away without any gradual build-up process it made no complaints about switching to the DOCP setting in the AI Tweaker menu in BIOS.

After the OS (W7/U64) was installed the 4-way Optimizer in AI Suite 3 produced an automated 103x45 overclock of CPU:4635/RAM:2472/VCore:1.512/GPU:1013 giving a performance boost of 13%.

Perhaps the real point about A88X is just its place in the development of APU boards.

[Mech0z]

An important thing is the ability to change TPD on the CPU aka lower power consumption which is important on a HTPC, not sure why you are complaining about limited overclock when we are talking using it on HTPC, then that should be pretty pointless at least for me.

MY FM2+ build idles at 26-28W with a 400W PSU (Dont think its worth it to use 100$ to get a PicoPSU)
http://www.overclock.net/t/1448459/m...-htpc-26w-idle

This build is both a NAS and HTPC which that motherboard is perfect for with HDMI IN, 6 SATA and mSATA

[chinook]

Actually i was refferring to a ATX FM2+ board which i was interested in (for overclocking the upcoming APU, overclocking RAM, etc).
I was under the impression that the thread was about FM2+ chipset specs and differences over previous chipsets, not specifically HTPC builds.
Sorry Dave, if i derailed your thread.

[Daveburt714]

Actually i was refferring to a ATX FM2+ board which i was interested in (for overclocking the upcoming APU, overclocking RAM, etc).
I was under the impression that the thread was about FM2+ chipset specs and differences over previous chipsets, not specifically HTPC builds.
Sorry Dave, if i derailed your thread.

No Problem chinook...

This build was about an HTPC, but my chipset question was about Kaveri, so I don't think you were OT at all!
Kinda sucks having to buy a board (chipset) for an UN-released processor, but it is what it is...

If the "piledriver/APU" cores do a decent job with lower power consumption I'll be a happy camper and would consider a new mobo too.

[FlanK3r]

The internal clockgen(s) has existed since SB600.
The issue is not about internal clockgen being used but the AHCI/RAID controller itself.
It always operates at the BCLK frequency no matter if the CLKIN frequency is sourced from a external or one of the internal clockgens. The FCH cannot use multiple clockgens simultaneously it is either the external or one of the internals.

It was the same for Ax5(X) series chipsets, however the AHCI/RAID controller in Ax5(X) could withstand up to 140MHz BCLK.

The internal clockgens found in Jaguar and newer SoCs is much more smarter.
All of the different frequencies can be adjusted separately in relation to BCLK (PCI-E, DISPCLK, SATA, USB, etc).

confirm it from practice in last days...

[justapost]

Same here, when using AHCI the BCLK limit is exact 106MHz, with IDE legacy it's 140MHz and that worked fine with an external pcie gfx card as well, so i assume pcie clocks are generated separated from BCLK. Read that by using BCLK as the base for other clock's helps with powersaving because the other clocksources can be powered off. Still i'm curious if it could be possible to configure the AHCI clocks to use the oscilator's direct via an bios modification. It's abit odd that this option was available (but not used) before and is available on all the mobile chipsets.

[filmbot]

The A88X chipset offers nothing new compared to A85X.
In fact it is worse than it's predecessor.

A88X has an upgraded AHCI / RAID controller which makes it unable (as it currently appears) to run over 106MHz BCLK while AHCI is enabled. Personally I would rather see the top tier FM2+ motherboard using A85X FCH instead of the A88X.

So does this mean A85X will fully support Kaveri out of the box or with BIOS update? If you have K SKU chip does the BCLK limit mean that much?

Looking to upgrade a family members rig that will have light to mild OC but nothing else too stressful. So would like to know which one to go with.

[FlanK3r]

A85X are not FM2+ boards, only A88x are FM2+

max multiplier is 63x and this not must be enough for LN2 tweaking. Max memory divider is 2400 MHz I think with Kaveri APU, but you need sometimes more...Kaveri, seems, will have not problem working with 2666 MHz for 24/7.

[justapost]

Dave hope you dont mind if i post fm2+ chipset related stuff in your thread here.
Received an Asrock FM2A88X Extreme6+ today. Had also orderen an kaveri but that one was out of stock as soon as i had hit order. So i tested with a4-4000. Selected AHCI in the bios gave it an fresh install and it seems this board can handle higher bclk frequencies. It uses amd-sata and not msahci but it works well upto the boards max bclk 136MHz. At 133MHz however the network interface stops working. Also tried it with linux from an usb3 stick but there the ahci module is still not working with the high bclk.

[msimax]

A85X are not FM2+ boards, only A88x are FM2+

max multiplier is 63x and this not must be enough for LN2 tweaking. Max memory divider is 2400 MHz I think with Kaveri APU, but you need sometimes more...Kaveri, seems, will have not problem working with 2666 MHz for 24/7.

the gigabyte board im using has a max multi of x79 or is some not usable??

[FlanK3r]

with Kaveri chip? Its strange...I think, max multiplier for 15h is 63x