View Full Version : Overclocking

08-06-2007, 10:25 AM
Hey folks looking at new CPU's and does anyone know if overclocking
the cpu effects the timing inside of SE?

I am not sure what is used to determine time but does overclocking mess
SE up?

Anyone running an overclocked system?

08-06-2007, 12:07 PM
We've got our SE system overclocked, it's running great.

08-06-2007, 12:17 PM
Yeah, overclocking should be pretty much transparent to applications...up unto the point where it causes instability, anyway.

08-06-2007, 05:44 PM
DirectX is ignorant to overclocking and SE proves this further.
Indeed, it has to be this way ever since speedstep technology came out.

Just because an NLE is a demanding application doesn't mean that SpeedStep or EIST won't kick in at any point in time. I/O bottlenecks almost guarantee this whether hanging around waiting to do something because running the timeline is just so easy, or whether held back due to the storage system not keeping up. So given that these situations do what can be regarded as a CPU underclock (in the Intel Core2 example, by reducing the multiplier). If timing loops were derived by cpu wait-spins then we'd have been lost for multimedia under windows a long time ago. Penryn based Core2 is about overclocking in a burst-mode too. So if speedstepping was a special case, there are more to follow.

No, really there is nothing to fear if you stay within the bounds of what your CPU, chipset, peripheral chips, graphics card and memory can handle 'on air' cooling. Let the younger generation find the bounds and then work towards doing something along the same lines yourself.

The new motherboards' chipset and Vista offer some super-accurate hardware timers. It would be likely that we'll see these employed by subsequent timing critical applications too.

Watch out for the benefits of the X38 chipsets, lowest latency DDR3 on a board that has enhancements geared towards overclocking (usually meaning ATX form factors from the usual Abit, DFI, ASUS, Gigabyte crusaders). Blended with something from the CPU ranks that is of an engineering calibre capable of matching the "Intel extreme" processor in the range but that is pitched at the near budget level (e.g. E6320 or E6600).

Although Penryn may change this, Quad Core Core2 CPUs aren' yet known for their overclockability. When applications have better threading than today, or at least - when their makers do things as well as NewTek's products do, then the advantages of cores over GHz will become more clear.

If you had a VT you'd be in the same situation but in times past - you might have had a timing issue or have trashed the card if you didn't keep it going at precisely 33MHz or 66MHz. While memory interfacing designs vary, keeping the PCI and PCIexpress timings at the intended values is relatively straightforward. IMHO, YMMV ! Although I'd recommend restricting such experiments to your SpeedEDIT workstation. At least until you are out of warranty, if VT's hardware is really ever out of warranty.

Dennis Sladek
08-06-2007, 08:03 PM
I'm running an Intel E4300 overclocked to 3.3 Ghz in a Gigabyte GA-965P-DS3 Motherboard. All is just fine with all editing applications.
I plan to stick in an Q6600 when the price settles, and I have more time.

My previous system was an overclocked dual core Opteron in a DFI Ultra NF4 Motherboard. That system was also rock solid.

08-07-2007, 04:54 AM
I am looking at the Q6600 as well and want to run the FSB to 1333
which would bring the clock up to 3.x Ghz Thats my goal.
What kind of cooling do you add? Is the memory special?
I am also looking at the NVidia 8800 or 8600
The motherboard I am looking at is the ASUS p35


John Perkins
08-07-2007, 08:38 AM
I've got to be the voice of reason here and say that if you overclock the system that you earn a living with, you are taking a huge risk.

It also makes troubleshooting harder because random crashes or graphical glitches can happen that are impossible to track down.

A few, unnoticeable Mhz is not worth my wasted time personally.

08-07-2007, 11:20 AM
THIS IS INADVISABLE IF YOU DON'T HAVE A BACKGROUND IN EITHER ELECTRONICS OR ATOMIC PHYSICS. You can still learn about it from the university of life, I mean google. It is when you take the informed decision and then come unstuck - that is when you'll wish you hadn't used your hot-rodding gene.

My experience is that the overclocking situation only gets better with the age of your computer. Talk of electron migration attempts to explain this but the main consideration is that you should not expect to hit the highest reported on-air figures on the same day as you assemble the computer.

If you hate having to return broken parts at all, don't even build a computer to run at stock levels. It really can work out to be rather expensive to return and claim shipping back and have to argue over whether you may have mishandled the install. Some screwdriver shops will build, overclock and warrant on that spec. There is always the option to bring things back to their rated values before you report an OS or application issue to the vendor. Fair is fair.

There is risk involved but only IMHO, where you chase temptation. Keeping inside the realms of fantasy will be unlikely to cause you an issue. However if you are cack handed with the building procedure or hell bent on keeping your machine silent, then you might not want to go down this route at all.

A 1.8GHz dual-core Core2 clocked at 3GHz on air is very reasonable to expect. A 2.4 quad-core Core2 clocked at 3GHz is about the same actually. As the process is OK, but until Penryn arrives, it is double-trouble under the hood.

For the first few days or weeks I run at stock levels. This allows the heat compound to settle in. For Core2, no more than a short grain of rice ideally of a premium compound. However a stock cooler usually does a good job - case dependent.

Run like that and observe temperatures. Ambient upto 50degC is normal. The CPU has thermal protection, but ought not to go above 72degC.

Clearly if you have a bug to report, you should only do so when you've repeated your problem at stock levels.

Memory, well this is where you weigh up your overall budget. You can grab the smallest Intel quad-core and the cheapest generic memory rated for your northbridge. However if you are going to (1333) 333 a (1066) 266 CPU then you need to know if your chipset supports the right divider or if it has an independent (async) clock generator for driving the RAM. Intel's own chipsets usually use a divider resource - and the BIOS needs to give you access to that. Or, you buy the PC2-10666 memory and keep the divider as if it were running PC2-8500 memory.

At this moment in time PC3-10666 memory has a CAS latency of 7 clocks and costs just over US$500 for 2x1GB. Follow the motherboards approved supplier list to a certain extent (this saves fiddling about - especially at the initial stock-levels. Especially as most DRAM seems to need more than the JEDEC 1.8V even at the sticker speeds).

Some graphics cards are already overclocked when you buy them (it usually says so). So do choose a motherboard that can fix PCIexpress to 100MHz. It is rare that PCI (on the southbridge) will change with FSB tweaking, but again - check that against the reports you read on the motherboard you are choosing. Overclocking an already overclocked (at the factory) graphics card is inadvisable.

I'd recommend using UltimateBootCD for Windows for soak testing your machine. This saves you having to risk disk errors on your hard drive. Although this should only happen if you take your FSB away from what the chipset was designed to perform at (and correspondingly the RAM and CPU if the clocks are fixed multiples). RAM doesn't usually clock to the next category up, but usually you can find that the latency can be pulled down a notch. However you'll add voltage to achieve this, and within months you can buy the same RAM, sell your old and the whole transaction costs less than a fancy cooler.

Folks love to claim that they've overclocked their class of processor above that of the equivalent Intel Extreme. The QX6700 was very much like the smaller varieties (cherry picked if you like). However the QX6800 at 2.93GHz has more in common with Clovertown from the reports. So you can't always assume that you are just fighting the marketing departments hobbling of an otherwise identical part. Sometimes Intel don't make the product range quite that much of a natural extension from lowest GHz to highest.

Do you need decent RAM, do you need a certain type of cooler. Well, pain for gain I'd say no you don't.

Personally I'd chase memory bandwidth before GHz. Especially in this NLE/content-creation industry. I'd also not worry to chase premium DirectX10 graphics cards personally. Sticking below $120 for your PEG.

So I'd look for a hybrid motherboard with 4 DDR3 sockets and two DDR2. Jumping on the DDR3 wagon when latencies are at CAS4 levels (ie where PC2-6400 is easily achieving now) with speed ratings in the PC3-16000 level for $200 for 4GB. A board like that would also be Penryn capable and would probably support PCIexpress 2.0 (double data rate and the ability to have bus extension cables to take the socket out of the PC chassis itself).

Bob, you mention the Q6600 and on a selection of P35 motherboards this CPU is reaching 3GHz. Chances are that X38 overclocking boards will only help this to be achievable. Q6600 stock values are hard to sniff at though, especially for the likes of what you'd be doing with NewTek software.

See if you can afford to go for CAS7 1333 rated DDR3 memory. Maybe you'll only get 2GB in there for a price you'll be prepared to pay. Otherwise get the lowest latency DDR2 1333 or 1066 memory (the latter if it really saves you a packet). Then SATA DMA from the ICH9R, CPU crunching and Shader 2.0 stuff will have the best chance at all the internal plumbing of your machine. That has to be good and you don't need to worry so much about racing your CPU, but that can still be an option.