I have my video card selection narrowed down to 5 cards; all are within my price range and have favorable reviews. I will be buying today after I receive feedback.
• 4 of them are the HD 4870’s with 512 MB of GDDR5, Core clock 750 MHz
• 1 of them is an HD 4850 with 1 GB of GDDR3, Core clock 625 MHz
The SAPPHIRE 100242-1GL Radeon HD 4850 1GB 256-bit GDDR3 looks to me like the best deal; twice the amount of memory, but only the MEM is slightly slower. Max resolution, core clock, and memory clock, about the same for all 5 cards.
When I look at the “end-user reviews” on this web site, there are a high number of reviews for the HD 4870 - 512 MB - GDDR5 cards and only 3 reviews for the HD 4850 – 1 GB –GDDR3 card. Both 4850 and 4870’s have favorable reviews, but obviously, most buyers opt for the HD 4870.
Why, I don’t understand?
Is there really that much performance difference between GDDR5 and GDDR3?
My video hungry software packages are Flight Simulator X, Punch Home Design, and F.E.A.R.
I see other users on this forum reveal online company names, so I think it’s safe to assume this is not a forum violation. My apology in advance if it is.
Proc = Core 2 Duo E6750 with Liquid Cooling System
MB = Gigabyte GA-P35-DQ6
Mem = Corsair, CM2X1024, 2 GB
HD= 2 SATA Barracuda 320 GB & WD 320 GB
Video = GeForce 8600 GT
Case/PSU = Smilodon Case w/500 Watt PSU
OS = Windows XP SP 3
More people prefer the 4870 primarily because of it's competition, the GTX260 by NVidia. According to most benchmarks, the 4870 is slightly faster than the GTX260 while also costing slightly less as well.
As for your games : Flight Simulator X, Punch Home Design, and F.E.A.R. . Both video cards would massacre them. As they are applications that are either CPU bound or older games that isn't as demanding on hardware.
Also it's kinda hard to comment on the 1GB 4850 as there's very little review of the video card comparing it to the vanilla 512MB. So it's very uncertain if the card can actually make use of the 1GB of VRAM.
Main things to consider here are what size screen and resolution are you using ? As that will have a bearing on your choice of card. Also worth a mention is that Flight Simulator X is a very CPU heavy and upping the GPU wont give you much in the way of a performance boost.
Im assuming the 6750 has a decent OC on it ?
Yes GDDR 5 is better than Gddr3 It is effectivly Quad pumped or X4 the acctual bus speed (thats not quite technically correct but its close enough for our purposes) which means it has more bandwidth even though there is less of it.
The screen size: my monitor is 22 inches and my plasma TV is 50 inches; I use them both as a monitor.
The Proc. 6750 is overclockable; although, I’ve never tried it. But I should, and is probable safe since I have a water cooler.
There is a review over at Guru3d about a 2GB version of the 4850, to be honest it doesn't seem to be worth it ( though its memory frequency is lower by 200mhz. Personally I think the 4870 would be the better purchase.
Another thing to consider is the fact that the 4850 is a single slot and will dump lots of heat into your case! The 4870 is a dual slot which expells the heat out the back.
Both cards use a 256bit bus which is effective for only 512 MB of vram, so you won't see much if anything with 1GB.
4870 all the way!
No heating problems at all. It’s just lacking in frame rates and resolution area (MS Flight Sim X ad F.E.A.R.) It’s also rather clunky as for the dual monitor option in its control panel (50 inch plasma and 22 inch monitor). It has crashed my system a few times (good thing I have Acronis imaging). XFX tech support is great and helpful, but they are limited to what the newest drivers and utilities can do.