AMD ATI Radeon HD 4890
Get ready for gigahertz graphics
Review The new AMD ATI Radeon HD 4890 is heavily based on the HD 4870 but it has some changes in its architecture that allow it to run substantially higher clock speeds.
How much higher? Glad you asked. The 4870 has reference clock speeds of 750MHz for the core and GDDR 5 memory that runs at 900MHz. GDDR 5 is a completely different animal to GDDR 3 so the 900MHz speed equates to an effective speed of 3600MHz. This business of true speed/effective speed could get wearisome so we’re going to stick to effective speeds for this review.
Asus' EAH4890: AMD's Radeon HD 4890 - aka 'RV790' - on board
A reference 4870 runs at 750MHz/3600MHz and a factory overclocked specimen runs a tad faster at 800MHz/4000MHz. You’ll generally find that you can overclock a decent 4870 to 850MHz/4300MHz.
By contrast, the new 4890 comes out of the blocks at 850MHz/3900MHz and is also available in factory overclocked versions with a 900MHz core and memory clocked at 4000MHz. Two weeks after the launch of 4890, we can expect to see a super overclocked variant that will run much faster. We estimate that a 1GHz core speed is quite plausible, with memory running at 4400MHz.
That’s a lot of numbers so let’s recap: a basic 4870 has speeds of 750MHz/3600MHz, and the Asus board we used for testing overclocked to 870MHz/4360MHz. The new 4890 starts at 850MHz/3900MHz, and our Asus sample overclocks to 980MHz/4480MHz.
That’s a useful speed bump and as the 4890 has the same 800 unified-shader stream processors and 256-bit memory controller as the 4870 does, we can expect the extra speed will give a proportional increase in performance.
COMMENTS
ATI card in my vista PC
Biggest hardware upgrade mistake I've ever made.
With catalyst installed, aero randomly crashes.
With catalyst uninstalled, I get other errors like black squares showing up occasionally around the cursor, video upscaling not rendering properly and my dual monitors not staying in place after a restart.
So, current solution is "Windows Classic" theme, which is kind of annoying, since I do actually like the look of aero, and the PC and card is fast enough to run it.
Vista and by extension, this driver problem, has been around for what, nearly 4 years now? And windows 7 also has aero, so the problem won't be going away anytime soon. The excuse of "it's Microsofts problem" is starting to wear a little thin.
@ Dave
Dell isn't in the business of selling PSU at retail, and tests true PSU capacity from it's suppliers. Therefore, what you're getting with a Dell PSU rated for 350W tends to be one that's actually capable of it, and the whole integrated system also tested to be lower consumption which makes sense as you wouldn't expect a quad core box with a 3650 in it to reach 275W peak, let alone 350W.
Typical power requirements cited by video card manufacturers are to shift the burden and expense of instable equipment to the owner, how easily they can tell someone to throw more money at a problem because there are so many PSU out there that don't live up to their ratings.
On the other hand, a modern system with a 4870 or 90 video card in it ought to have higher than 350W PSU powering it, but if/when the day comes that Dell integrated (term loosely used, not meaning soldered onto the mainboard) these 4890 into systems they will provide a beefy enough PSU to at least handle the one installed card even if it cannot support Crossfire.
@AC: Academic
I bought 2 Dell home machines with ATi 3650 cards (1 for dad, the other for a friend), BOTH had incorrectly installed ATI drivers that caused errors and crashes.
The problem is the piss-poor way that Dell install them, not necessarily the hardware. The thing to try is a complete un-install of the Dell supplied drivers. Then use DriverCleaner or similar to ensure that all the registry keys have been removed as well. Then restart, and then install a new fresh, Catalyst from ATI. Do NOT use Windows Update or a Dell driver. That should clear up the issues - well fingers crossed! It did for those two machines mentioned above.
If not, then Dell has this annoying tendency to use PSUs that are severely under-powered for the hardware (my Dell Studio not XPS is a quad core, 8GB ram with ATi 3650 and had a pathetic 350W PSU). Try changing the PSU to a 500W min, decent quality PSU. Should help no end or see here: http://ati.amd.com/products/radeonhd4800/requirements.html for power requirements for the HD4800 series.
4830 for todays budget concious
£300 on a gfx card is madness! I paid £70 for my 4830 (quidco for teh win) and it might not be the fastest kid on the block but will play happily in 1680x
I suppose I could Xfire it if I had a mobo but why bother - the mobo would cost just as much...
Telling them apart...
Apart from the obvious pictures on the heatsink/exhaust thing, the two silver things on the end of the cards(capacitors?) are different sizes on each card. Defy that!! :-)
